예제 #1
0
def Fkkt(W):

    # Factor 
    #
    #     S = A*D^-1*A' + I 
    #
    # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**2, D2 = d[n:]**2.

    d1, d2 = W['di'][:n]**2, W['di'][n:]**2    

    # ds is square root of diagonal of D
    ds = sqrt(2.0) * div( mul( W['di'][:n], W['di'][n:]), sqrt(d1+d2) )
    d3 =  div(d2 - d1, d1 + d2)
 
    # Asc = A*diag(d)^-1/2
    blas.copy(A, Asc)
    for k in range(m):
        blas.tbsv(ds, Asc, n=n, k=0, ldA=1, incx=m, offsetx=k)

    # S = I + A * D^-1 * A'
    blas.syrk(Asc, S)
    S[::m+1] += 1.0 
    lapack.potrf(S)

    def g(x, y, z):

        x[:n] = 0.5 * ( x[:n] - mul(d3, x[n:]) + \
                mul(d1, z[:n] + mul(d3, z[:n])) - \
                mul(d2, z[n:] - mul(d3, z[n:])) )
        x[:n] = div( x[:n], ds) 

        # Solve
        #
        #     S * v = 0.5 * A * D^-1 * ( bx[:n] 
        #             - (D2-D1)*(D1+D2)^-1 * bx[n:] 
        #             + D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bz[:n]
        #             - D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bz[n:] )
	    
        blas.gemv(Asc, x, v)
        lapack.potrs(S, v)
	
        # x[:n] = D^-1 * ( rhs - A'*v ).
        blas.gemv(Asc, v, x, alpha=-1.0, beta=1.0, trans='T')
        x[:n] = div(x[:n], ds)

        # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bz[:n]  - D2*bz[n:] )
        #         - (D2-D1)*(D1+D2)^-1 * x[:n]         
        x[n:] = div( x[n:] - mul(d1, z[:n]) - mul(d2, z[n:]), d1+d2 )\
                - mul( d3, x[:n] )
	    
        # z[:n] = D1^1/2 * (  x[:n] - x[n:] - bz[:n] )
        # z[n:] = D2^1/2 * ( -x[:n] - x[n:] - bz[n:] ).
        z[:n] = mul( W['di'][:n],  x[:n] - x[n:] - z[:n] ) 
        z[n:] = mul( W['di'][n:], -x[:n] - x[n:] - z[n:] ) 

    return g
def Fkkt(W):

    # Factor
    #
    #     S = A*D^-1*A' + I
    #
    # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**2, D2 = d[n:]**2.

    d1, d2 = W['di'][:n]**2, W['di'][n:]**2

    # ds is square root of diagonal of D
    ds = sqrt(2.0) * div(mul(W['di'][:n], W['di'][n:]), sqrt(d1 + d2))
    d3 = div(d2 - d1, d1 + d2)

    # Asc = A*diag(d)^-1/2
    blas.copy(A, Asc)
    for k in range(m):
        blas.tbsv(ds, Asc, n=n, k=0, ldA=1, incx=m, offsetx=k)

    # S = I + A * D^-1 * A'
    blas.syrk(Asc, S)
    S[::m + 1] += 1.0
    lapack.potrf(S)

    def g(x, y, z):

        x[:n] = 0.5 * ( x[:n] - mul(d3, x[n:]) + \
                mul(d1, z[:n] + mul(d3, z[:n])) - \
                mul(d2, z[n:] - mul(d3, z[n:])) )
        x[:n] = div(x[:n], ds)

        # Solve
        #
        #     S * v = 0.5 * A * D^-1 * ( bx[:n]
        #             - (D2-D1)*(D1+D2)^-1 * bx[n:]
        #             + D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bz[:n]
        #             - D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bz[n:] )

        blas.gemv(Asc, x, v)
        lapack.potrs(S, v)

        # x[:n] = D^-1 * ( rhs - A'*v ).
        blas.gemv(Asc, v, x, alpha=-1.0, beta=1.0, trans='T')
        x[:n] = div(x[:n], ds)

        # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bz[:n]  - D2*bz[n:] )
        #         - (D2-D1)*(D1+D2)^-1 * x[:n]
        x[n:] = div( x[n:] - mul(d1, z[:n]) - mul(d2, z[n:]), d1+d2 )\
                - mul( d3, x[:n] )

        # z[:n] = D1^1/2 * (  x[:n] - x[n:] - bz[:n] )
        # z[n:] = D2^1/2 * ( -x[:n] - x[n:] - bz[n:] ).
        z[:n] = mul(W['di'][:n], x[:n] - x[n:] - z[:n])
        z[n:] = mul(W['di'][n:], -x[:n] - x[n:] - z[n:])

    return g
예제 #3
0
def d_kernel(R, k, norm=True):
    
    m = R.size[0]
    n = R.size[1]
    
    x_choose_k = [0]*(n+1)
    x_choose_k[0] = 0
    for i in range(1, n+1):
        x_choose_k[i] = spc.binom(i,k)
    
    nCk = x_choose_k[n]
    X = R*R.T
    
    K = co.matrix(0.0, (X.size[0], X.size[1]))
    for i in range(m):
        for j in range(i, m):
            n_niCk = x_choose_k[n - int(X[i,i])]
            n_njCk = x_choose_k[n - int(X[j,j])]
            n_ni_nj_nijCk = x_choose_k[n - int(X[i,i]) - int(X[j,j]) + int(X[i,j])]
            K[i,j] = K[j,i] = nCk - n_niCk - n_njCk + n_ni_nj_nijCk
    
    if norm:
        YY = co.matrix([K[i,i] for i in range(K.size[0])])
        YY = co.sqrt(YY)**(-1)
        K = co.mul(K, YY*YY.T)

    return K
예제 #4
0
 def F(x=None, z=None):
     if x is None: return 0, matrix(0.0, (n, 1))
     y = A * x - b
     w = sqrt(rho + y**2)
     f = sum(w)
     Df = div(y, w).T * A
     if z is None: return f, Df
     H = A.T * spdiag(z[0] * rho * (w**-3)) * A
     return f, Df, H
예제 #5
0
파일: cvx.py 프로젝트: makgyver/pyros
def normalize_rows(X):
	"""
	@param X: the matrix
	@type X: cvxopt dense matrix
	@return: the row-normalized matrix
	@rtype: cvxopt dense matrix
	"""
	d = diagonal_vec(X*X.T)
	N = co.sqrt(d * ones_vec(X.size[1]).T)
	return co.div(X,N)
예제 #6
0
def normalize_cols(X):
    """
	@param X: the matrix
	@type X: cvxopt dense matrix
	@return: the col-normalized matrix
	@rtype: cvxopt dense matrix
	"""
    d = diagonal_vec(X.T * X)
    N = co.sqrt(ones_vec(X.size[0]) * d.T)
    return co.div(X, N)
예제 #7
0
파일: cvx.py 프로젝트: makgyver/pyros
def normalize_cols(X):
	"""
	@param X: the matrix
	@type X: cvxopt dense matrix
	@return: the col-normalized matrix
	@rtype: cvxopt dense matrix
	"""
	d = diagonal_vec(X.T*X)
	N = co.sqrt(ones_vec(X.size[0])*d.T)
	return co.div(X,N)
예제 #8
0
def normalize_rows(X):
    """
	@param X: the matrix
	@type X: cvxopt dense matrix
	@return: the row-normalized matrix
	@rtype: cvxopt dense matrix
	"""
    d = diagonal_vec(X * X.T)
    N = co.sqrt(d * ones_vec(X.size[1]).T)
    return co.div(X, N)
예제 #9
0
    def Fkkt(W):

        # Factor
        #
        #     S = A*D^-1*A' + I
        #
        # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**-2, D2 = d[n:]**-2.

        d1, d2 = W['di'][:n]**2, W['di'][n:]**2
        print 'printing: ', W['di']

        # ds is square root of diagonal of D
        ds = math.sqrt(2.0) * div(mul(W['di'][:n], W['di'][n:]), sqrt(d1 + d2))
        d3 = div(d2 - d1, d1 + d2)

        Asc = matrix(0.0, (m, n))
        # Asc = A*diag(d)^-1/2
        Asc = A * spdiag(ds**-1)

        # S = I + A * D^-1 * A'
        blas.syrk(Asc, S)
        S[::m + 1] += 1.0
        lapack.potrf(S)

        def g(x, y, z):

            x[:n] = 0.5 * (x[:n] - mul(d3, x[n:]) + mul(
                d1, z[:n] + mul(d3, z[:n])) - mul(d2, z[n:] - mul(d3, z[n:])))
            x[:n] = div(x[:n], ds)

            # Solve
            #
            #     S * v = 0.5 * A * D^-1 * ( bx[:n] -
            #         (D2-D1)*(D1+D2)^-1 * bx[n:] +
            #         D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bzl[:n] -
            #         D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bzl[n:] )

            blas.gemv(Asc, x, v)
            lapack.potrs(S, v)

            # x[:n] = D^-1 * ( rhs - A'*v ).
            blas.gemv(Asc, v, x, alpha=-1.0, beta=1.0, trans='T')
            x[:n] = div(x[:n], ds)

            # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bzl[:n]  - D2*bzl[n:] )
            #         - (D2-D1)*(D1+D2)^-1 * x[:n]
            x[n:] = div( x[n:] - mul(d1, z[:n]) - mul(d2, z[n:]), d1+d2 )\
                - mul( d3, x[:n] )

            # zl[:n] = D1^1/2 * (  x[:n] - x[n:] - bzl[:n] )
            # zl[n:] = D2^1/2 * ( -x[:n] - x[n:] - bzl[n:] ).
            z[:n] = mul(W['di'][:n], x[:n] - x[n:] - z[:n])
            z[n:] = mul(W['di'][n:], -x[:n] - x[n:] - z[n:])

        return g
예제 #10
0
파일: l1regls.py 프로젝트: sanurielf/cvxopt
    def Fkkt(W):

        # Factor 
        #
        #     S = A*D^-1*A' + I 
        #
        # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**-2, D2 = d[n:]**-2.

        d1, d2 = W['di'][:n]**2, W['di'][n:]**2

        # ds is square root of diagonal of D
        ds = math.sqrt(2.0) * div( mul( W['di'][:n], W['di'][n:]), 
            sqrt(d1+d2) )
        d3 =  div(d2 - d1, d1 + d2)
     
        # Asc = A*diag(d)^-1/2
        Asc = A * spdiag(ds**-1)

        # S = I + A * D^-1 * A'
        blas.syrk(Asc, S)
        S[::m+1] += 1.0 
        lapack.potrf(S)

        def g(x, y, z):

            x[:n] = 0.5 * ( x[:n] - mul(d3, x[n:]) + 
                mul(d1, z[:n] + mul(d3, z[:n])) - mul(d2, z[n:] - 
                mul(d3, z[n:])) )
            x[:n] = div( x[:n], ds) 

            # Solve
            #
            #     S * v = 0.5 * A * D^-1 * ( bx[:n] - 
            #         (D2-D1)*(D1+D2)^-1 * bx[n:] + 
            #         D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bzl[:n] - 
            #         D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bzl[n:] )
                
            blas.gemv(Asc, x, v)
            lapack.potrs(S, v)
            
            # x[:n] = D^-1 * ( rhs - A'*v ).
            blas.gemv(Asc, v, x, alpha=-1.0, beta=1.0, trans='T')
            x[:n] = div(x[:n], ds)

            # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bzl[:n]  - D2*bzl[n:] ) 
            #         - (D2-D1)*(D1+D2)^-1 * x[:n]         
            x[n:] = div( x[n:] - mul(d1, z[:n]) - mul(d2, z[n:]), d1+d2 )\
                - mul( d3, x[:n] )
                
            # zl[:n] = D1^1/2 * (  x[:n] - x[n:] - bzl[:n] )
            # zl[n:] = D2^1/2 * ( -x[:n] - x[n:] - bzl[n:] ).
            z[:n] = mul( W['di'][:n],  x[:n] - x[n:] - z[:n] ) 
            z[n:] = mul( W['di'][n:], -x[:n] - x[n:] - z[n:] ) 

        return g
예제 #11
0
파일: l1.py 프로젝트: Ovec8hkin/PySAR
    def Fkkt(W):

        # Returns a function f(x, y, z) that solves
        #
        # [ 0  0  P'      -P'      ] [ x[:n] ]   [ bx[:n] ]
        # [ 0  0 -I       -I       ] [ x[n:] ]   [ bx[n:] ]
        # [ P -I -D1^{-1}  0       ] [ z[:m] ] = [ bz[:m] ]
        # [-P -I  0       -D2^{-1} ] [ z[m:] ]   [ bz[m:] ]
        #
        # where D1 = diag(di[:m])^2, D2 = diag(di[m:])^2 and di = W['di'].
        #
        # On entry bx, bz are stored in x, z.
        # On exit x, z contain the solution, with z scaled (di .* z is
        # returned instead of z).

        # Factor A = 4*P'*D*P where D = d1.*d2 ./(d1+d2) and
        # d1 = d[:m].^2, d2 = d[m:].^2.

        di = W['di']
        d1, d2 = di[:m]**2, di[m:]**2
        D = div(mul(d1, d2), d1 + d2)
        Ds = spdiag(2 * sqrt(D))
        base.gemm(Ds, P, Ps)
        blas.syrk(Ps, A, trans='T')
        lapack.potrf(A)

        def f(x, y, z):

            # Solve for x[:n]:
            #
            #    A*x[:n] = bx[:n] + P' * ( ((D1-D2)*(D1+D2)^{-1})*bx[n:]
            #        + (2*D1*D2*(D1+D2)^{-1}) * (bz[:m] - bz[m:]) ).

            blas.copy((mul(div(d1 - d2, d1 + d2), x[n:]) +
                       mul(2 * D, z[:m] - z[m:])), u)
            blas.gemv(P, u, x, beta=1.0, trans='T')
            lapack.potrs(A, x)

            # x[n:] := (D1+D2)^{-1} * (bx[n:] - D1*bz[:m] - D2*bz[m:]
            #     + (D1-D2)*P*x[:n])

            base.gemv(P, x, u)
            x[n:] = div(
                x[n:] - mul(d1, z[:m]) - mul(d2, z[m:]) + mul(d1 - d2, u),
                d1 + d2)

            # z[:m] := d1[:m] .* ( P*x[:n] - x[n:] - bz[:m])
            # z[m:] := d2[m:] .* (-P*x[:n] - x[n:] - bz[m:])

            z[:m] = mul(di[:m], u - x[n:] - z[:m])
            z[m:] = mul(di[m:], -u - x[n:] - z[m:])

        return f
예제 #12
0
파일: l1.py 프로젝트: cuihantao/cvxopt
    def Fkkt(W): 

        # Returns a function f(x, y, z) that solves
        #
        # [ 0  0  P'      -P'      ] [ x[:n] ]   [ bx[:n] ]
        # [ 0  0 -I       -I       ] [ x[n:] ]   [ bx[n:] ]
        # [ P -I -D1^{-1}  0       ] [ z[:m] ] = [ bz[:m] ]
        # [-P -I  0       -D2^{-1} ] [ z[m:] ]   [ bz[m:] ]
        #
        # where D1 = diag(di[:m])^2, D2 = diag(di[m:])^2 and di = W['di'].
        #
        # On entry bx, bz are stored in x, z.
        # On exit x, z contain the solution, with z scaled (di .* z is
        # returned instead of z). 

        # Factor A = 4*P'*D*P where D = d1.*d2 ./(d1+d2) and
        # d1 = d[:m].^2, d2 = d[m:].^2.

        di = W['di']
        d1, d2 = di[:m]**2, di[m:]**2
        D = div( mul(d1,d2), d1+d2 )  
        Ds = spdiag(2 * sqrt(D))
        base.gemm(Ds, P, Ps)
        blas.syrk(Ps, A, trans = 'T')
        lapack.potrf(A)

        def f(x, y, z):

            # Solve for x[:n]:
            #
            #    A*x[:n] = bx[:n] + P' * ( ((D1-D2)*(D1+D2)^{-1})*bx[n:]
            #        + (2*D1*D2*(D1+D2)^{-1}) * (bz[:m] - bz[m:]) ).

            blas.copy(( mul( div(d1-d2, d1+d2), x[n:]) + 
                mul( 2*D, z[:m]-z[m:] ) ), u)
            blas.gemv(P, u, x, beta = 1.0, trans = 'T')
            lapack.potrs(A, x)

            # x[n:] := (D1+D2)^{-1} * (bx[n:] - D1*bz[:m] - D2*bz[m:]
            #     + (D1-D2)*P*x[:n])

            base.gemv(P, x, u)
            x[n:] =  div( x[n:] - mul(d1, z[:m]) - mul(d2, z[m:]) + 
                mul(d1-d2, u), d1+d2 )

            # z[:m] := d1[:m] .* ( P*x[:n] - x[n:] - bz[:m])
            # z[m:] := d2[m:] .* (-P*x[:n] - x[n:] - bz[m:]) 

            z[:m] = mul(di[:m],  u-x[n:]-z[:m])
            z[m:] = mul(di[m:], -u-x[n:]-z[m:])

        return f
예제 #13
0
파일: kernels.py 프로젝트: wsgan001/pyros
def normalize(K):
    """
	@param K: the matrix
	@type K: cvxopt dense matrix or numpy array
	@return: the row-normalized matrix
	@rtype: cvxopt dense matrix
	"""
    if type(K) is np.ndarray:
        d = np.array([[K[i, i] for i in range(K.shape[0])]])
        return K / np.sqrt(np.dot(d.T, d))
    else:
        YY = cvx.diagonal_vec(K)
        YY = co.sqrt(YY)**(-1)
        return co.mul(K, YY * YY.T)
예제 #14
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def normalize_cols_sparse(X):
    """
	@param X: the matrix
	@type X: cvxopt matrix
	@return: the col-normalized matrix
	@rtype: cvxopt sparse matrix
	"""
    d = co.matrix([sum(X[:, i].V) for i in xrange(X.size[1])])
    N = co.sqrt(d.T)
    I, J = X.I, X.J
    V = []
    for j in X.J:
        V += [(1.0 / N[j]) if N[j] != 0.0 else 0.0]
    return co.spmatrix(V, I, J)
예제 #15
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파일: kernels.py 프로젝트: makgyver/pyros
def normalize(K):
	"""
	@param K: the matrix
	@type K: cvxopt dense matrix or numpy array
	@return: the row-normalized matrix
	@rtype: cvxopt dense matrix
	"""
	if type(K) is np.ndarray:
		d = np.array([[K[i,i] for i in range(K.shape[0])]])
		return K / np.sqrt(np.dot(d.T,d))
	else:
		YY = cvx.diagonal_vec(K)
		YY = co.sqrt(YY)**(-1)
		return co.mul(K, YY*YY.T)	
예제 #16
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파일: cvx.py 프로젝트: makgyver/pyros
def normalize_cols_sparse(X):
	"""
	@param X: the matrix
	@type X: cvxopt matrix
	@return: the col-normalized matrix
	@rtype: cvxopt sparse matrix
	"""
	d = co.matrix([sum(X[:,i].V) for i in xrange(X.size[1])])
	N = co.sqrt(d.T)
	I, J = X.I, X.J
	V = []
	for j in X.J:
		V += [(1.0 / N[j]) if N[j] != 0.0 else 0.0]
	return co.spmatrix(V, I, J)
예제 #17
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# least squares solution:  minimize || A*x - b ||_2^2
xls = +b 
lapack.gels(+A, xls)
xls = xls[:n]

# Tikhonov solution:  minimize || A*x - b ||_2^2 + 0.1*||x||^2_2
xtik = A.T*b
S = A.T*A
S[::n+1] += 0.1
lapack.posv(S, xtik)

# Worst case solution
xwc = wcls(A, Ap, b)

notrials = 100000
r = sqrt(uniform(1,notrials))
theta = 2.0 * pi * uniform(1,notrials)
u = matrix(0.0, (2,notrials))
u[0,:] = mul(r, cos(theta))
u[1,:] = mul(r, sin(theta))

# LS solution 
q = A*xls - b
P = matrix(0.0, (m,2))
P[:,0], P[:,1] = Ap[0]*xls, Ap[1]*xls
r = P*u + q[:,notrials*[0]]
resls = sqrt( matrix(1.0, (1,m)) * mul(r,r) )

q = A*xtik - b
P[:,0], P[:,1] = Ap[0]*xtik, Ap[1]*xtik
r = P*u + q[:,notrials*[0]]
예제 #18
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    # Figures for linear placement.

    pylab.figure(1, figsize=(10, 4), facecolor='w')
    pylab.subplot(121)
    X = matrix(0.0, (N + M, 2))
    X[:N, :], X[N:, :] = X1, Xf
    pylab.plot(Xf[:, 0], Xf[:, 1], 'sw', mec='k')
    pylab.plot(X1[:, 0], X1[:, 1], 'or', ms=10)
    for s, t in E:
        pylab.plot([X[s, 0], X[t, 0]], [X[s, 1], X[t, 1]], 'b:')
    pylab.axis([-1.1, 1.1, -1.1, 1.1])
    pylab.axis('equal')
    pylab.title('Linear placement')

    pylab.subplot(122)
    lngths = sqrt((A1 * X1 + B)**2 * matrix(1.0, (2, 1)))
    pylab.hist(list(lngths), [.1 * k for k in range(15)])
    x = pylab.arange(0, 1.6, 1.6 / 500)
    pylab.plot(x, 5.0 / 1.6 * x, '--k')
    pylab.axis([0, 1.6, 0, 5.5])
    pylab.title('Length distribution')

    # Figures for quadratic placement.

    pylab.figure(2, figsize=(10, 4), facecolor='w')
    pylab.subplot(121)
    X[:N, :], X[N:, :] = X2, Xf
    pylab.plot(Xf[:, 0], Xf[:, 1], 'sw', mec='k')
    pylab.plot(X2[:, 0], X2[:, 1], 'or', ms=10)
    for s, t in E:
        pylab.plot([X[s, 0], X[t, 0]], [X[s, 1], X[t, 1]], 'b:')
예제 #19
0
파일: ubsdp.py 프로젝트: wsgan001/itce2011
    def F(W):
        """
        Generate a solver for

                                             A'(uz0) = bx[0]
                                          -uz0 - uz1 = bx[1] 
            A(ux[0]) - ux[1] - r0*r0' * uz0 * r0*r0' = bz0 
                     - ux[1] - r1*r1' * uz1 * r1*r1' = bz1.

        uz0, uz1, bz0, bz1 are symmetric m x m-matrices.
        ux[0], bx[0] are n-vectors.
        ux[1], bx[1] are symmetric m x m-matrices.

        We first calculate a congruence that diagonalizes r0*r0' and r1*r1':
 
            U' * r0 * r0' * U = I,  U' * r1 * r1' * U = S.

        We then make a change of variables

            usx[0] = ux[0],  
            usx[1] = U' * ux[1] * U  
              usz0 = U^-1 * uz0 * U^-T  
              usz1 = U^-1 * uz1 * U^-T 

        and define 

              As() = U' * A() * U'  
            bsx[1] = U^-1 * bx[1] * U^-T
              bsz0 = U' * bz0 * U  
              bsz1 = U' * bz1 * U.  

        This gives

                             As'(usz0) = bx[0]
                          -usz0 - usz1 = bsx[1] 
            As(usx[0]) - usx[1] - usz0 = bsz0 
                -usx[1] - S * usz1 * S = bsz1.


        1. Eliminate usz0, usz1 using equations 3 and 4,

               usz0 = As(usx[0]) - usx[1] - bsz0
               usz1 = -S^-1 * (usx[1] + bsz1) * S^-1.

           This gives two equations in usx[0] an usx[1].

               As'(As(usx[0]) - usx[1]) = bx[0] + As'(bsz0)

               -As(usx[0]) + usx[1] + S^-1 * usx[1] * S^-1
                   = bsx[1] - bsz0 - S^-1 * bsz1 * S^-1.


        2. Eliminate usx[1] using equation 2:

               usx[1] + S * usx[1] * S 
                   = S * ( As(usx[0]) + bsx[1] - bsz0 ) * S - bsz1

           i.e., with Gamma[i,j] = 1.0 + S[i,i] * S[j,j],
 
               usx[1] = ( S * As(usx[0]) * S ) ./ Gamma 
                        + ( S * ( bsx[1] - bsz0 ) * S - bsz1 ) ./ Gamma.

           This gives an equation in usx[0].

               As'( As(usx[0]) ./ Gamma ) 
                   = bx0 + As'(bsz0) + 
                     As'( (S * ( bsx[1] - bsz0 ) * S - bsz1) ./ Gamma )
                   = bx0 + As'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ Gamma ).

        """

        # Calculate U s.t.
        #
        #     U' * r0*r0' * U = I,   U' * r1*r1' * U = diag(s).

        # Cholesky factorization r0 * r0' = L * L'
        blas.syrk(W['r'][0], L)
        lapack.potrf(L)

        # SVD L^-1 * r1 = U * diag(s) * V'
        blas.copy(W['r'][1], U)
        blas.trsm(L, U)
        lapack.gesvd(U, s, jobu='O')

        # s := s**2
        s[:] = s**2

        # Uti := U
        blas.copy(U, Uti)

        # U := L^-T * U
        blas.trsm(L, U, transA='T')

        # Uti := L * Uti = U^-T
        blas.trmm(L, Uti)

        # Us := U * diag(s)^-1
        blas.copy(U, Us)
        for i in range(m):
            blas.tbsv(s, Us, n=m, k=0, ldA=1, incx=m, offsetx=i)

        # S is m x m with lower triangular entries s[i] * s[j]
        # sqrtG is m x m with lower triangular entries sqrt(1.0 + s[i]*s[j])
        # Upper triangular entries are undefined but nonzero.

        blas.scal(0.0, S)
        blas.syrk(s, S)
        Gamma = 1.0 + S
        sqrtG = sqrt(Gamma)

        # Asc[i] = (U' * Ai * * U ) ./  sqrtG,  for i = 1, ..., n
        #        = Asi ./ sqrt(Gamma)
        blas.copy(A, Asc)
        misc.scale(
            Asc,  # only 'r' part of the dictionary is used   
            {
                'dnl': matrix(0.0, (0, 1)),
                'dnli': matrix(0.0, (0, 1)),
                'd': matrix(0.0, (0, 1)),
                'di': matrix(0.0, (0, 1)),
                'v': [],
                'beta': [],
                'r': [U],
                'rti': [U]
            })
        for i in range(n):
            blas.tbsv(sqrtG, Asc, n=msq, k=0, ldA=1, offsetx=i * msq)

        # Convert columns of Asc to packed storage
        misc.pack2(Asc, {'l': 0, 'q': [], 's': [m]})

        # Cholesky factorization of Asc' * Asc.
        H = matrix(0.0, (n, n))
        blas.syrk(Asc, H, trans='T', k=mpckd)
        lapack.potrf(H)

        def solve(x, y, z):
            """

            1. Solve for usx[0]:

               Asc'(Asc(usx[0]))
                   = bx0 + Asc'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ sqrtG)
                   = bx0 + Asc'( ( bsz0 + S * ( bsx[1] - bssz1) S ) 
                     ./ sqrtG)

               where bsx[1] = U^-1 * bx[1] * U^-T, bsz0 = U' * bz0 * U, 
               bsz1 = U' * bz1 * U, bssz1 = S^-1 * bsz1 * S^-1 

            2. Solve for usx[1]:

               usx[1] + S * usx[1] * S 
                   = S * ( As(usx[0]) + bsx[1] - bsz0 ) * S - bsz1 

               usx[1] 
                   = ( S * (As(usx[0]) + bsx[1] - bsz0) * S - bsz1) ./ Gamma
                   = -bsz0 + (S * As(usx[0]) * S) ./ Gamma
                     + (bsz0 - bsz1 + S * bsx[1] * S ) . / Gamma
                   = -bsz0 + (S * As(usx[0]) * S) ./ Gamma
                     + (bsz0 + S * ( bsx[1] - bssz1 ) * S ) . / Gamma

               Unscale ux[1] = Uti * usx[1] * Uti'

            3. Compute usz0, usz1

               r0' * uz0 * r0 = r0^-1 * ( A(ux[0]) - ux[1] - bz0 ) * r0^-T
               r1' * uz1 * r1 = r1^-1 * ( -ux[1] - bz1 ) * r1^-T

            """

            # z0 := U' * z0 * U
            #     = bsz0
            __cngrnc(U, z, trans='T')

            # z1 := Us' * bz1 * Us
            #     = S^-1 * U' * bz1 * U * S^-1
            #     = S^-1 * bsz1 * S^-1
            __cngrnc(Us, z, trans='T', offsetx=msq)

            # x[1] := Uti' * x[1] * Uti
            #       = bsx[1]
            __cngrnc(Uti, x[1], trans='T')

            # x[1] := x[1] - z[msq:]
            #       = bsx[1] - S^-1 * bsz1 * S^-1
            blas.axpy(z, x[1], alpha=-1.0, offsetx=msq)

            # x1 = (S * x[1] * S + z[:msq] ) ./ sqrtG
            #    = (S * ( bsx[1] - S^-1 * bsz1 * S^-1) * S + bsz0 ) ./ sqrtG
            #    = (S * bsx[1] * S - bsz1 + bsz0 ) ./ sqrtG
            # in packed storage
            blas.copy(x[1], x1)
            blas.tbmv(S, x1, n=msq, k=0, ldA=1)
            blas.axpy(z, x1, n=msq)
            blas.tbsv(sqrtG, x1, n=msq, k=0, ldA=1)
            misc.pack2(x1, {'l': 0, 'q': [], 's': [m]})

            # x[0] := x[0] + Asc'*x1
            #       = bx0 + Asc'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ sqrtG)
            #       = bx0 + As'( ( bz0 - bz1 + S * bx[1] * S ) ./ Gamma )
            blas.gemv(Asc, x1, x[0], m=mpckd, trans='T', beta=1.0)

            # x[0] := H^-1 * x[0]
            #       = ux[0]
            lapack.potrs(H, x[0])

            # x1 = Asc(x[0]) .* sqrtG  (unpacked)
            #    = As(x[0])
            blas.gemv(Asc, x[0], tmp, m=mpckd)
            misc.unpack(tmp, x1, {'l': 0, 'q': [], 's': [m]})
            blas.tbmv(sqrtG, x1, n=msq, k=0, ldA=1)

            # usx[1] = (x1 + (x[1] - z[:msq])) ./ sqrtG**2
            #        = (As(ux[0]) + bsx[1] - bsz0 - S^-1 * bsz1 * S^-1)
            #           ./ Gamma

            # x[1] := x[1] - z[:msq]
            #       = bsx[1] - bsz0 - S^-1 * bsz1 * S^-1
            blas.axpy(z, x[1], -1.0, n=msq)

            # x[1] := x[1] + x1
            #       = As(ux) + bsx[1] - bsz0 - S^-1 * bsz1 * S^-1
            blas.axpy(x1, x[1])

            # x[1] := x[1] / Gammma
            #       = (As(ux) + bsx[1] - bsz0 + S^-1 * bsz1 * S^-1 ) / Gamma
            #       = S^-1 * usx[1] * S^-1
            blas.tbsv(Gamma, x[1], n=msq, k=0, ldA=1)

            # z[msq:] := r1' * U * (-z[msq:] - x[1]) * U * r1
            #         := -r1' * U * S^-1 * (bsz1 + ux[1]) * S^-1 *  U * r1
            #         := -r1' * uz1 * r1
            blas.axpy(x[1], z, n=msq, offsety=msq)
            blas.scal(-1.0, z, offset=msq)
            __cngrnc(U, z, offsetx=msq)
            __cngrnc(W['r'][1], z, trans='T', offsetx=msq)

            # x[1] :=  S * x[1] * S
            #       =  usx1
            blas.tbmv(S, x[1], n=msq, k=0, ldA=1)

            # z[:msq] = r0' * U' * ( x1 - x[1] - z[:msq] ) * U * r0
            #         = r0' * U' * ( As(ux) - usx1 - bsz0 ) * U * r0
            #         = r0' * U' *  usz0 * U * r0
            #         = r0' * uz0 * r0
            blas.axpy(x1, z, -1.0, n=msq)
            blas.scal(-1.0, z, n=msq)
            blas.axpy(x[1], z, -1.0, n=msq)
            __cngrnc(U, z)
            __cngrnc(W['r'][0], z, trans='T')

            # x[1] := Uti * x[1] * Uti'
            #       = ux[1]
            __cngrnc(Uti, x[1])

        return solve
예제 #20
0
    def F(W):
        """
        Create a solver for the linear equations

                                C * ux + G' * uzl - 2*A'(uzs21) = bx
                                                         -uzs11 = bX1
                                                         -uzs22 = bX2
                                            G * ux - Dl^2 * uzl = bzl
            [ -uX1   -A(ux)' ]          [ uzs11 uzs21' ]     
            [                ] - r*r' * [              ] * r*r' = bzs
            [ -A(ux) -uX2    ]          [ uzs21 uzs22  ]

        where Dl = diag(W['l']), r = W['r'][0].  

        On entry, x = (bx, bX1, bX2) and z = [ bzl; bzs[:] ].
        On exit, x = (ux, uX1, uX2) and z = [ Dl*uzl; (r'*uzs*r)[:] ].


        1. Compute matrices V1, V2 such that (with T = r*r')
        
               [ V1   0   ] [ T11  T21' ] [ V1'  0  ]   [ I  S' ]
               [          ] [           ] [         ] = [       ]
               [ 0    V2' ] [ T21  T22  ] [ 0    V2 ]   [ S  I  ]
        
           and S = [ diag(s); 0 ], s a positive q-vector.

        2. Factor the mapping X -> X + S * X' * S:

               X + S * X' * S = L( L'( X )). 

        3. Compute scaled mappings: a matrix As with as its columns the 
           coefficients of the scaled mapping 

               L^-1( V2' * A() * V1' ) 

           and the matrix Gs = Dl^-1 * G.

        4. Cholesky factorization of H = C + Gs'*Gs + 2*As'*As.

        """


        # 1. Compute V1, V2, s.  

        r = W['r'][0]

        # LQ factorization R[:q, :] = L1 * Q1.
        lapack.lacpy(r, Q1, m = q)
        lapack.gelqf(Q1, tau1)
        lapack.lacpy(Q1, L1, n = q, uplo = 'L')
        lapack.orglq(Q1, tau1)

        # LQ factorization R[q:, :] = L2 * Q2.
        lapack.lacpy(r, Q2, m = p, offsetA = q)
	lapack.gelqf(Q2, tau2)
        lapack.lacpy(Q2, L2, n = p, uplo = 'L')
        lapack.orglq(Q2, tau2)


        # V2, V1, s are computed from an SVD: if
        # 
        #     Q2 * Q1' = U * diag(s) * V',
        #
        # then V1 = V' * L1^-1 and V2 = L2^-T * U.
    
        # T21 = Q2 * Q1.T  
        blas.gemm(Q2, Q1, T21, transB = 'T')

        # SVD T21 = U * diag(s) * V'.  Store U in V2 and V' in V1.
        lapack.gesvd(T21, s, jobu = 'A', jobvt = 'A', U = V2, Vt = V1) 

#        # Q2 := Q2 * Q1' without extracting Q1; store T21 in Q2
#        this will requires lapack.ormlq or lapack.unmlq

        # V2 = L2^-T * U   
        blas.trsm(L2, V2, transA = 'T') 

        # V1 = V' * L1^-1 
        blas.trsm(L1, V1, side = 'R') 


        # 2. Factorization X + S * X' * S = L( L'( X )).  
        #
        # The factor L is stored as a diagonal matrix D and a sparse lower 
        # triangular matrix P, such that  
        #
        #     L(X)[:] = D**-1 * (I + P) * X[:] 
        #     L^-1(X)[:] = D * (I - P) * X[:].

        # SS is q x q with SS[i,j] = si*sj.
        blas.scal(0.0, SS)
        blas.syr(s, SS)    
        
        # For a p x q matrix X, P*X[:] is Y[:] where 
        #
        #     Yij = si * sj * Xji  if i < j
        #         = 0              otherwise.
        # 
        P.V = SS[Itril2]

        # For a p x q matrix X, D*X[:] is Y[:] where 
        #
        #     Yij = Xij / sqrt( 1 - si^2 * sj^2 )  if i < j
        #         = Xii / sqrt( 1 + si^2 )         if i = j
        #         = Xij                            otherwise.
        # 
        DV[Idiag] = sqrt(1.0 + SS[::q+1])
        DV[Itriu] = sqrt(1.0 - SS[Itril3]**2)
        D.V = DV**-1


        # 3. Scaled linear mappings 
         
        # Ask :=  V2' * Ask * V1' 
        blas.scal(0.0, As)
        base.axpy(A, As)
        for i in xrange(n):
            # tmp := V2' * As[i, :]
            blas.gemm(V2, As, tmp, transA = 'T', m = p, n = q, k = p,
                ldB = p, offsetB = i*p*q)
            # As[:,i] := tmp * V1'
            blas.gemm(tmp, V1, As, transB = 'T', m = p, n = q, k = q,
                ldC = p, offsetC = i*p*q)

        # As := D * (I - P) * As 
        #     = L^-1 * As.
        blas.copy(As, As2)
        base.gemm(P, As, As2, alpha = -1.0, beta = 1.0)
        base.gemm(D, As2, As)

        # Gs := Dl^-1 * G 
        blas.scal(0.0, Gs)
        base.axpy(G, Gs)
        for k in xrange(n):
            blas.tbmv(W['di'], Gs, n = m, k = 0, ldA = 1, offsetx = k*m)


        # 4. Cholesky factorization of H = C + Gs' * Gs + 2 * As' * As.

        blas.syrk(As, H, trans = 'T', alpha = 2.0)
        blas.syrk(Gs, H, trans = 'T', beta = 1.0)
        base.axpy(C, H)   
        lapack.potrf(H)


        def f(x, y, z):
            """

            Solve 

                              C * ux + G' * uzl - 2*A'(uzs21) = bx
                                                       -uzs11 = bX1
                                                       -uzs22 = bX2
                                           G * ux - D^2 * uzl = bzl
                [ -uX1   -A(ux)' ]       [ uzs11 uzs21' ]     
                [                ] - T * [              ] * T = bzs.
                [ -A(ux) -uX2    ]       [ uzs21 uzs22  ]

            On entry, x = (bx, bX1, bX2) and z = [ bzl; bzs[:] ].
            On exit, x = (ux, uX1, uX2) and z = [ D*uzl; (r'*uzs*r)[:] ].

            Define X = uzs21, Z = T * uzs * T:   
 
                      C * ux + G' * uzl - 2*A'(X) = bx
                                [ 0  X' ]               [ bX1 0   ]
                            T * [       ] * T - Z = T * [         ] * T
                                [ X  0  ]               [ 0   bX2 ]
                               G * ux - D^2 * uzl = bzl
                [ -uX1   -A(ux)' ]   [ Z11 Z21' ]     
                [                ] - [          ] = bzs
                [ -A(ux) -uX2    ]   [ Z21 Z22  ]

            Return x = (ux, uX1, uX2), z = [ D*uzl; (rti'*Z*rti)[:] ].

            We use the congruence transformation 

                [ V1   0   ] [ T11  T21' ] [ V1'  0  ]   [ I  S' ]
                [          ] [           ] [         ] = [       ]
                [ 0    V2' ] [ T21  T22  ] [ 0    V2 ]   [ S  I  ]

            and the factorization 

                X + S * X' * S = L( L'(X) ) 

            to write this as

                                  C * ux + G' * uzl - 2*A'(X) = bx
                L'(V2^-1 * X * V1^-1) - L^-1(V2' * Z21 * V1') = bX
                                           G * ux - D^2 * uzl = bzl
                            [ -uX1   -A(ux)' ]   [ Z11 Z21' ]     
                            [                ] - [          ] = bzs,
                            [ -A(ux) -uX2    ]   [ Z21 Z22  ]

            or

                C * ux + Gs' * uuzl - 2*As'(XX) = bx
                                      XX - ZZ21 = bX
                                 Gs * ux - uuzl = D^-1 * bzl
                                 -As(ux) - ZZ21 = bbzs_21
                                     -uX1 - Z11 = bzs_11
                                     -uX2 - Z22 = bzs_22

            if we introduce scaled variables

                uuzl = D * uzl
                  XX = L'(V2^-1 * X * V1^-1) 
                     = L'(V2^-1 * uzs21 * V1^-1)
                ZZ21 = L^-1(V2' * Z21 * V1') 

            and define

                bbzs_21 = L^-1(V2' * bzs_21 * V1')
                                           [ bX1  0   ]
                     bX = L^-1( V2' * (T * [          ] * T)_21 * V1').
                                           [ 0    bX2 ]           
 
            Eliminating Z21 gives 

                C * ux + Gs' * uuzl - 2*As'(XX) = bx
                                 Gs * ux - uuzl = D^-1 * bzl
                                   -As(ux) - XX = bbzs_21 - bX
                                     -uX1 - Z11 = bzs_11
                                     -uX2 - Z22 = bzs_22 

            and eliminating uuzl and XX gives

                        H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bX - bbzs_21)
                Gs * ux - uuzl = D^-1 * bzl
                  -As(ux) - XX = bbzs_21 - bX
                    -uX1 - Z11 = bzs_11
                    -uX2 - Z22 = bzs_22.


            In summary, we can use the following algorithm: 

            1. bXX := bX - bbzs21
                                        [ bX1 0   ]
                    = L^-1( V2' * ((T * [         ] * T)_21 - bzs_21) * V1')
                                        [ 0   bX2 ]

            2. Solve H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bXX).

            3. From ux, compute 

                   uuzl = Gs*ux - D^-1 * bzl and 
                      X = V2 * L^-T(-As(ux) + bXX) * V1.

            4. Return ux, uuzl, 

                   rti' * Z * rti = r' * [ -bX1, X'; X, -bX2 ] * r
 
               and uX1 = -Z11 - bzs_11,  uX2 = -Z22 - bzs_22.

            """

            # Save bzs_11, bzs_22, bzs_21.
            lapack.lacpy(z, bz11, uplo = 'L', m = q, n = q, ldA = p+q,
                offsetA = m)
            lapack.lacpy(z, bz21, m = p, n = q, ldA = p+q, offsetA = m+q)
            lapack.lacpy(z, bz22, uplo = 'L', m = p, n = p, ldA = p+q,
                offsetA = m + (p+q+1)*q)


            # zl := D^-1 * zl
            #     = D^-1 * bzl
            blas.tbmv(W['di'], z, n = m, k = 0, ldA = 1)


            # zs := r' * [ bX1, 0; 0, bX2 ] * r.

            # zs := [ bX1, 0; 0, bX2 ]
            blas.scal(0.0, z, offset = m)
            lapack.lacpy(x[1], z, uplo = 'L', m = q, n = q, ldB = p+q,
                offsetB = m)
            lapack.lacpy(x[2], z, uplo = 'L', m = p, n = p, ldB = p+q,
                offsetB = m + (p+q+1)*q)

            # scale diagonal of zs by 1/2
            blas.scal(0.5, z, inc = p+q+1, offset = m)

            # a := tril(zs)*r  
            blas.copy(r, a)
            blas.trmm(z, a, side = 'L', m = p+q, n = p+q, ldA = p+q, ldB = 
                p+q, offsetA = m)

            # zs := a'*r + r'*a 
            blas.syr2k(r, a, z, trans = 'T', n = p+q, k = p+q, ldB = p+q,
                ldC = p+q, offsetC = m)



            # bz21 := L^-1( V2' * ((r * zs * r')_21 - bz21) * V1')
            #
            #                           [ bX1 0   ]
            #       = L^-1( V2' * ((T * [         ] * T)_21 - bz21) * V1').
            #                           [ 0   bX2 ]

            # a = [ r21 r22 ] * z
            #   = [ r21 r22 ] * r' * [ bX1, 0; 0, bX2 ] * r
            #   = [ T21  T22 ] * [ bX1, 0; 0, bX2 ] * r
            blas.symm(z, r, a, side = 'R', m = p, n = p+q, ldA = p+q, 
                ldC = p+q, offsetB = q)
    
            # bz21 := -bz21 + a * [ r11, r12 ]'
            #       = -bz21 + (T * [ bX1, 0; 0, bX2 ] * T)_21
            blas.gemm(a, r, bz21, transB = 'T', m = p, n = q, k = p+q, 
                beta = -1.0, ldA = p+q, ldC = p)

            # bz21 := V2' * bz21 * V1'
            #       = V2' * (-bz21 + (T*[bX1, 0; 0, bX2]*T)_21) * V1'
            blas.gemm(V2, bz21, tmp, transA = 'T', m = p, n = q, k = p, 
                ldB = p)
            blas.gemm(tmp, V1, bz21, transB = 'T', m = p, n = q, k = q, 
                ldC = p)

            # bz21[:] := D * (I-P) * bz21[:] 
            #       = L^-1 * bz21[:]
            #       = bXX[:]
            blas.copy(bz21, tmp)
            base.gemv(P, bz21, tmp, alpha = -1.0, beta = 1.0)
            base.gemv(D, tmp, bz21)


            # Solve H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bXX).

            # x[0] := x[0] + Gs'*zl + 2*As'(bz21) 
            #       = bx + G' * D^-1 * bzl + 2 * As'(bXX)
            blas.gemv(Gs, z, x[0], trans = 'T', alpha = 1.0, beta = 1.0)
            blas.gemv(As, bz21, x[0], trans = 'T', alpha = 2.0, beta = 1.0) 

            # x[0] := H \ x[0] 
            #      = ux
            lapack.potrs(H, x[0])


            # uuzl = Gs*ux - D^-1 * bzl
            blas.gemv(Gs, x[0], z, alpha = 1.0, beta = -1.0)

            
            # bz21 := V2 * L^-T(-As(ux) + bz21) * V1
            #       = X
            blas.gemv(As, x[0], bz21, alpha = -1.0, beta = 1.0)
            blas.tbsv(DV, bz21, n = p*q, k = 0, ldA = 1)
            blas.copy(bz21, tmp)
            base.gemv(P, tmp, bz21, alpha = -1.0, beta = 1.0, trans = 'T')
            blas.gemm(V2, bz21, tmp)
            blas.gemm(tmp, V1, bz21)


            # zs := -zs + r' * [ 0, X'; X, 0 ] * r
            #     = r' * [ -bX1, X'; X, -bX2 ] * r.

            # a := bz21 * [ r11, r12 ]
            #   =  X * [ r11, r12 ]
            blas.gemm(bz21, r, a, m = p, n = p+q, k = q, ldA = p, ldC = p+q)
            
            # z := -z + [ r21, r22 ]' * a + a' * [ r21, r22 ]
            #    = rti' * uzs * rti
            blas.syr2k(r, a, z, trans = 'T', beta = -1.0, n = p+q, k = p,
                offsetA = q, offsetC = m, ldB = p+q, ldC = p+q)  



            # uX1 = -Z11 - bzs_11 
            #     = -(r*zs*r')_11 - bzs_11
            # uX2 = -Z22 - bzs_22 
            #     = -(r*zs*r')_22 - bzs_22


            blas.copy(bz11, x[1])
            blas.copy(bz22, x[2])

            # scale diagonal of zs by 1/2
            blas.scal(0.5, z, inc = p+q+1, offset = m)

            # a := r*tril(zs)  
            blas.copy(r, a)
            blas.trmm(z, a, side = 'R', m = p+q, n = p+q, ldA = p+q, ldB = 
                p+q, offsetA = m)

            # x[1] := -x[1] - a[:q,:] * r[:q, :]' - r[:q,:] * a[:q,:]'
            #       = -bzs_11 - (r*zs*r')_11
            blas.syr2k(a, r, x[1], n = q, alpha = -1.0, beta = -1.0) 

            # x[2] := -x[2] - a[q:,:] * r[q:, :]' - r[q:,:] * a[q:,:]'
            #       = -bzs_22 - (r*zs*r')_22
            blas.syr2k(a, r, x[2], n = p, alpha = -1.0, beta = -1.0, 
                offsetA = q, offsetB = q)

            # scale diagonal of zs by 1/2
            blas.scal(2.0, z, inc = p+q+1, offset = m)


        return f
예제 #21
0
    def F(W):
        """
        Create a solver for the linear equations

                                C * ux + G' * uzl - 2*A'(uzs21) = bx
                                                         -uzs11 = bX1
                                                         -uzs22 = bX2
                                            G * ux - Dl^2 * uzl = bzl
            [ -uX1   -A(ux)' ]          [ uzs11 uzs21' ]     
            [                ] - r*r' * [              ] * r*r' = bzs
            [ -A(ux) -uX2    ]          [ uzs21 uzs22  ]

        where Dl = diag(W['l']), r = W['r'][0].  

        On entry, x = (bx, bX1, bX2) and z = [ bzl; bzs[:] ].
        On exit, x = (ux, uX1, uX2) and z = [ Dl*uzl; (r'*uzs*r)[:] ].


        1. Compute matrices V1, V2 such that (with T = r*r')
        
               [ V1   0   ] [ T11  T21' ] [ V1'  0  ]   [ I  S' ]
               [          ] [           ] [         ] = [       ]
               [ 0    V2' ] [ T21  T22  ] [ 0    V2 ]   [ S  I  ]
        
           and S = [ diag(s); 0 ], s a positive q-vector.

        2. Factor the mapping X -> X + S * X' * S:

               X + S * X' * S = L( L'( X )). 

        3. Compute scaled mappings: a matrix As with as its columns the 
           coefficients of the scaled mapping 

               L^-1( V2' * A() * V1' ) 

           and the matrix Gs = Dl^-1 * G.

        4. Cholesky factorization of H = C + Gs'*Gs + 2*As'*As.

        """

        # 1. Compute V1, V2, s.

        r = W['r'][0]

        # LQ factorization R[:q, :] = L1 * Q1.
        lapack.lacpy(r, Q1, m=q)
        lapack.gelqf(Q1, tau1)
        lapack.lacpy(Q1, L1, n=q, uplo='L')
        lapack.orglq(Q1, tau1)

        # LQ factorization R[q:, :] = L2 * Q2.
        lapack.lacpy(r, Q2, m=p, offsetA=q)
        lapack.gelqf(Q2, tau2)
        lapack.lacpy(Q2, L2, n=p, uplo='L')
        lapack.orglq(Q2, tau2)

        # V2, V1, s are computed from an SVD: if
        #
        #     Q2 * Q1' = U * diag(s) * V',
        #
        # then V1 = V' * L1^-1 and V2 = L2^-T * U.

        # T21 = Q2 * Q1.T
        blas.gemm(Q2, Q1, T21, transB='T')

        # SVD T21 = U * diag(s) * V'.  Store U in V2 and V' in V1.
        lapack.gesvd(T21, s, jobu='A', jobvt='A', U=V2, Vt=V1)

        #        # Q2 := Q2 * Q1' without extracting Q1; store T21 in Q2
        #        this will requires lapack.ormlq or lapack.unmlq

        # V2 = L2^-T * U
        blas.trsm(L2, V2, transA='T')

        # V1 = V' * L1^-1
        blas.trsm(L1, V1, side='R')

        # 2. Factorization X + S * X' * S = L( L'( X )).
        #
        # The factor L is stored as a diagonal matrix D and a sparse lower
        # triangular matrix P, such that
        #
        #     L(X)[:] = D**-1 * (I + P) * X[:]
        #     L^-1(X)[:] = D * (I - P) * X[:].

        # SS is q x q with SS[i,j] = si*sj.
        blas.scal(0.0, SS)
        blas.syr(s, SS)

        # For a p x q matrix X, P*X[:] is Y[:] where
        #
        #     Yij = si * sj * Xji  if i < j
        #         = 0              otherwise.
        #
        P.V = SS[Itril2]

        # For a p x q matrix X, D*X[:] is Y[:] where
        #
        #     Yij = Xij / sqrt( 1 - si^2 * sj^2 )  if i < j
        #         = Xii / sqrt( 1 + si^2 )         if i = j
        #         = Xij                            otherwise.
        #
        DV[Idiag] = sqrt(1.0 + SS[::q + 1])
        DV[Itriu] = sqrt(1.0 - SS[Itril3]**2)
        D.V = DV**-1

        # 3. Scaled linear mappings

        # Ask :=  V2' * Ask * V1'
        blas.scal(0.0, As)
        base.axpy(A, As)
        for i in xrange(n):
            # tmp := V2' * As[i, :]
            blas.gemm(V2,
                      As,
                      tmp,
                      transA='T',
                      m=p,
                      n=q,
                      k=p,
                      ldB=p,
                      offsetB=i * p * q)
            # As[:,i] := tmp * V1'
            blas.gemm(tmp,
                      V1,
                      As,
                      transB='T',
                      m=p,
                      n=q,
                      k=q,
                      ldC=p,
                      offsetC=i * p * q)

        # As := D * (I - P) * As
        #     = L^-1 * As.
        blas.copy(As, As2)
        base.gemm(P, As, As2, alpha=-1.0, beta=1.0)
        base.gemm(D, As2, As)

        # Gs := Dl^-1 * G
        blas.scal(0.0, Gs)
        base.axpy(G, Gs)
        for k in xrange(n):
            blas.tbmv(W['di'], Gs, n=m, k=0, ldA=1, offsetx=k * m)

        # 4. Cholesky factorization of H = C + Gs' * Gs + 2 * As' * As.

        blas.syrk(As, H, trans='T', alpha=2.0)
        blas.syrk(Gs, H, trans='T', beta=1.0)
        base.axpy(C, H)
        lapack.potrf(H)

        def f(x, y, z):
            """

            Solve 

                              C * ux + G' * uzl - 2*A'(uzs21) = bx
                                                       -uzs11 = bX1
                                                       -uzs22 = bX2
                                           G * ux - D^2 * uzl = bzl
                [ -uX1   -A(ux)' ]       [ uzs11 uzs21' ]     
                [                ] - T * [              ] * T = bzs.
                [ -A(ux) -uX2    ]       [ uzs21 uzs22  ]

            On entry, x = (bx, bX1, bX2) and z = [ bzl; bzs[:] ].
            On exit, x = (ux, uX1, uX2) and z = [ D*uzl; (r'*uzs*r)[:] ].

            Define X = uzs21, Z = T * uzs * T:   
 
                      C * ux + G' * uzl - 2*A'(X) = bx
                                [ 0  X' ]               [ bX1 0   ]
                            T * [       ] * T - Z = T * [         ] * T
                                [ X  0  ]               [ 0   bX2 ]
                               G * ux - D^2 * uzl = bzl
                [ -uX1   -A(ux)' ]   [ Z11 Z21' ]     
                [                ] - [          ] = bzs
                [ -A(ux) -uX2    ]   [ Z21 Z22  ]

            Return x = (ux, uX1, uX2), z = [ D*uzl; (rti'*Z*rti)[:] ].

            We use the congruence transformation 

                [ V1   0   ] [ T11  T21' ] [ V1'  0  ]   [ I  S' ]
                [          ] [           ] [         ] = [       ]
                [ 0    V2' ] [ T21  T22  ] [ 0    V2 ]   [ S  I  ]

            and the factorization 

                X + S * X' * S = L( L'(X) ) 

            to write this as

                                  C * ux + G' * uzl - 2*A'(X) = bx
                L'(V2^-1 * X * V1^-1) - L^-1(V2' * Z21 * V1') = bX
                                           G * ux - D^2 * uzl = bzl
                            [ -uX1   -A(ux)' ]   [ Z11 Z21' ]     
                            [                ] - [          ] = bzs,
                            [ -A(ux) -uX2    ]   [ Z21 Z22  ]

            or

                C * ux + Gs' * uuzl - 2*As'(XX) = bx
                                      XX - ZZ21 = bX
                                 Gs * ux - uuzl = D^-1 * bzl
                                 -As(ux) - ZZ21 = bbzs_21
                                     -uX1 - Z11 = bzs_11
                                     -uX2 - Z22 = bzs_22

            if we introduce scaled variables

                uuzl = D * uzl
                  XX = L'(V2^-1 * X * V1^-1) 
                     = L'(V2^-1 * uzs21 * V1^-1)
                ZZ21 = L^-1(V2' * Z21 * V1') 

            and define

                bbzs_21 = L^-1(V2' * bzs_21 * V1')
                                           [ bX1  0   ]
                     bX = L^-1( V2' * (T * [          ] * T)_21 * V1').
                                           [ 0    bX2 ]           
 
            Eliminating Z21 gives 

                C * ux + Gs' * uuzl - 2*As'(XX) = bx
                                 Gs * ux - uuzl = D^-1 * bzl
                                   -As(ux) - XX = bbzs_21 - bX
                                     -uX1 - Z11 = bzs_11
                                     -uX2 - Z22 = bzs_22 

            and eliminating uuzl and XX gives

                        H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bX - bbzs_21)
                Gs * ux - uuzl = D^-1 * bzl
                  -As(ux) - XX = bbzs_21 - bX
                    -uX1 - Z11 = bzs_11
                    -uX2 - Z22 = bzs_22.


            In summary, we can use the following algorithm: 

            1. bXX := bX - bbzs21
                                        [ bX1 0   ]
                    = L^-1( V2' * ((T * [         ] * T)_21 - bzs_21) * V1')
                                        [ 0   bX2 ]

            2. Solve H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bXX).

            3. From ux, compute 

                   uuzl = Gs*ux - D^-1 * bzl and 
                      X = V2 * L^-T(-As(ux) + bXX) * V1.

            4. Return ux, uuzl, 

                   rti' * Z * rti = r' * [ -bX1, X'; X, -bX2 ] * r
 
               and uX1 = -Z11 - bzs_11,  uX2 = -Z22 - bzs_22.

            """

            # Save bzs_11, bzs_22, bzs_21.
            lapack.lacpy(z, bz11, uplo='L', m=q, n=q, ldA=p + q, offsetA=m)
            lapack.lacpy(z, bz21, m=p, n=q, ldA=p + q, offsetA=m + q)
            lapack.lacpy(z,
                         bz22,
                         uplo='L',
                         m=p,
                         n=p,
                         ldA=p + q,
                         offsetA=m + (p + q + 1) * q)

            # zl := D^-1 * zl
            #     = D^-1 * bzl
            blas.tbmv(W['di'], z, n=m, k=0, ldA=1)

            # zs := r' * [ bX1, 0; 0, bX2 ] * r.

            # zs := [ bX1, 0; 0, bX2 ]
            blas.scal(0.0, z, offset=m)
            lapack.lacpy(x[1], z, uplo='L', m=q, n=q, ldB=p + q, offsetB=m)
            lapack.lacpy(x[2],
                         z,
                         uplo='L',
                         m=p,
                         n=p,
                         ldB=p + q,
                         offsetB=m + (p + q + 1) * q)

            # scale diagonal of zs by 1/2
            blas.scal(0.5, z, inc=p + q + 1, offset=m)

            # a := tril(zs)*r
            blas.copy(r, a)
            blas.trmm(z,
                      a,
                      side='L',
                      m=p + q,
                      n=p + q,
                      ldA=p + q,
                      ldB=p + q,
                      offsetA=m)

            # zs := a'*r + r'*a
            blas.syr2k(r,
                       a,
                       z,
                       trans='T',
                       n=p + q,
                       k=p + q,
                       ldB=p + q,
                       ldC=p + q,
                       offsetC=m)

            # bz21 := L^-1( V2' * ((r * zs * r')_21 - bz21) * V1')
            #
            #                           [ bX1 0   ]
            #       = L^-1( V2' * ((T * [         ] * T)_21 - bz21) * V1').
            #                           [ 0   bX2 ]

            # a = [ r21 r22 ] * z
            #   = [ r21 r22 ] * r' * [ bX1, 0; 0, bX2 ] * r
            #   = [ T21  T22 ] * [ bX1, 0; 0, bX2 ] * r
            blas.symm(z,
                      r,
                      a,
                      side='R',
                      m=p,
                      n=p + q,
                      ldA=p + q,
                      ldC=p + q,
                      offsetB=q)

            # bz21 := -bz21 + a * [ r11, r12 ]'
            #       = -bz21 + (T * [ bX1, 0; 0, bX2 ] * T)_21
            blas.gemm(a,
                      r,
                      bz21,
                      transB='T',
                      m=p,
                      n=q,
                      k=p + q,
                      beta=-1.0,
                      ldA=p + q,
                      ldC=p)

            # bz21 := V2' * bz21 * V1'
            #       = V2' * (-bz21 + (T*[bX1, 0; 0, bX2]*T)_21) * V1'
            blas.gemm(V2, bz21, tmp, transA='T', m=p, n=q, k=p, ldB=p)
            blas.gemm(tmp, V1, bz21, transB='T', m=p, n=q, k=q, ldC=p)

            # bz21[:] := D * (I-P) * bz21[:]
            #       = L^-1 * bz21[:]
            #       = bXX[:]
            blas.copy(bz21, tmp)
            base.gemv(P, bz21, tmp, alpha=-1.0, beta=1.0)
            base.gemv(D, tmp, bz21)

            # Solve H * ux = bx + Gs' * D^-1 * bzl + 2*As'(bXX).

            # x[0] := x[0] + Gs'*zl + 2*As'(bz21)
            #       = bx + G' * D^-1 * bzl + 2 * As'(bXX)
            blas.gemv(Gs, z, x[0], trans='T', alpha=1.0, beta=1.0)
            blas.gemv(As, bz21, x[0], trans='T', alpha=2.0, beta=1.0)

            # x[0] := H \ x[0]
            #      = ux
            lapack.potrs(H, x[0])

            # uuzl = Gs*ux - D^-1 * bzl
            blas.gemv(Gs, x[0], z, alpha=1.0, beta=-1.0)

            # bz21 := V2 * L^-T(-As(ux) + bz21) * V1
            #       = X
            blas.gemv(As, x[0], bz21, alpha=-1.0, beta=1.0)
            blas.tbsv(DV, bz21, n=p * q, k=0, ldA=1)
            blas.copy(bz21, tmp)
            base.gemv(P, tmp, bz21, alpha=-1.0, beta=1.0, trans='T')
            blas.gemm(V2, bz21, tmp)
            blas.gemm(tmp, V1, bz21)

            # zs := -zs + r' * [ 0, X'; X, 0 ] * r
            #     = r' * [ -bX1, X'; X, -bX2 ] * r.

            # a := bz21 * [ r11, r12 ]
            #   =  X * [ r11, r12 ]
            blas.gemm(bz21, r, a, m=p, n=p + q, k=q, ldA=p, ldC=p + q)

            # z := -z + [ r21, r22 ]' * a + a' * [ r21, r22 ]
            #    = rti' * uzs * rti
            blas.syr2k(r,
                       a,
                       z,
                       trans='T',
                       beta=-1.0,
                       n=p + q,
                       k=p,
                       offsetA=q,
                       offsetC=m,
                       ldB=p + q,
                       ldC=p + q)

            # uX1 = -Z11 - bzs_11
            #     = -(r*zs*r')_11 - bzs_11
            # uX2 = -Z22 - bzs_22
            #     = -(r*zs*r')_22 - bzs_22

            blas.copy(bz11, x[1])
            blas.copy(bz22, x[2])

            # scale diagonal of zs by 1/2
            blas.scal(0.5, z, inc=p + q + 1, offset=m)

            # a := r*tril(zs)
            blas.copy(r, a)
            blas.trmm(z,
                      a,
                      side='R',
                      m=p + q,
                      n=p + q,
                      ldA=p + q,
                      ldB=p + q,
                      offsetA=m)

            # x[1] := -x[1] - a[:q,:] * r[:q, :]' - r[:q,:] * a[:q,:]'
            #       = -bzs_11 - (r*zs*r')_11
            blas.syr2k(a, r, x[1], n=q, alpha=-1.0, beta=-1.0)

            # x[2] := -x[2] - a[q:,:] * r[q:, :]' - r[q:,:] * a[q:,:]'
            #       = -bzs_22 - (r*zs*r')_22
            blas.syr2k(a,
                       r,
                       x[2],
                       n=p,
                       alpha=-1.0,
                       beta=-1.0,
                       offsetA=q,
                       offsetB=q)

            # scale diagonal of zs by 1/2
            blas.scal(2.0, z, inc=p + q + 1, offset=m)

        return f
예제 #22
0
    def solve(self, solver = "mosek"):
        if self.to_real == False: raise ValueError("Solvers do not support complex-valued data.")
        sol = {}
        c,G,h,dims = self.problem_data
        if solver == "mosek":
            if self.__verbose:
               msk.options[msk.mosek.iparam.log] = 1
            else:
               msk.options[msk.mosek.iparam.log] = 0
            solsta,mu,zz = msk.conelp(c,G,matrix(h),dims)
            sol['status'] = str(solsta).split('.')[-1]
        elif solver == "cvxopt":
            if self.__verbose:
                options = {'show_progress':True}
            else:
                options = {'show_progress':False}
            csol = solvers.conelp(c,G,matrix(h),dims,options=options)
            zz = csol['z']
            mu = csol['x']
            sol['status'] = csol['status']
        else:
            raise ValueError("Unknown solver %s" % (solver))
        if zz is None: return sol

        sol['mu'] = mu
        offset = self.offset
        sol['t'] = zz[:offset['wpl']]
        sol['wpl'] = zz[offset['wpl']:offset['wpu']]
        sol['wpu'] = zz[offset['wpu']:offset['wql']]
        sol['wql'] = zz[offset['wql']:offset['wqu']]
        sol['wqu'] = zz[offset['wqu']:offset['ul']]
        sol['ul'] = zz[offset['ul']:offset['uu']]
        sol['uu'] = zz[offset['uu']:offset['z']]
        sol['z'] = zz[offset['z']:offset['w']]
        sol['w'] = zz[offset['w']:offset['X']]

        if self.conversion:
            dims = self.problem_data[3]
            offset = dims['l'] + sum(dims['q'])
            self.Xc = []
            sol['eigratio'] = []
            for k,sk in enumerate(dims['s']):
                zk = matrix(zz[offset:offset+sk**2],(sk,sk))
                offset += sk**2
                zkr = 0.5*(zk[:sk//2,:sk//2] + zk[sk//2:,sk//2:])
                zki = 0.5*(zk[sk//2:,:sk//2] - zk[:sk//2,sk//2:])
                zki[::sk+1] = 0.0
                zk = zkr + complex(0,1.0)*zki
                self.Xc.append(zk)
                ev = matrix(0.0,(zk.size[0],1),tc='d')
                lapack.heev(+zk,ev)
                ev = sorted(list(ev),reverse=True)
                sol['eigratio'].append(ev[0]/ev[1])

            # Build partial Hermitian matrix
            z = matrix([zk[:] for zk in self.Xc])
            blki,I,J,bn = self.blocks_to_sparse[0]
            X = spmatrix(z[blki],I,J)
            idx = [i for i,ij in enumerate(zip(X.I,X.J)) if ij[0] > ij[1]]
            sol['X'] = chompack.tril(X) + spmatrix(X.V[idx].H, X.J[idx], X.I[idx], X.size)

        else:
            X = matrix(zz[offset['X']:],(2*self.nbus,2*self.nbus))
            Xr = X[:self.nbus,:self.nbus]
            Xi = X[self.nbus:,:self.nbus]
            Xi[::self.nbus+1] = 0.0
            X = Xr + complex(0.0,1.0)*Xi
            sol['X'] = +X

            V = matrix(0.0,(self.nbus,5),tc='z')
            w = matrix(0.0,(self.nbus,1))
            lapack.heevr(X, w, Z = V, jobz='V', range='I', il = self.nbus-4, iu = self.nbus)
            sol['eigratio'] = [w[4]/w[3]]
            if w[4]/w[3] < self.eigtol and self.__verbose:
                print("Eigenvalue ratio smaller than %e."%(self.eigtol))
            sol['eigs'] = w[:5]
            V = V[:,-1]*sqrt(w[4])
            sol['V'] = V

        # Branch injections
        sol['Sf'] = self.baseMVA*(sol['z'][1::6] + complex(0.0,1.0)*sol['z'][2::6])
        sol['St'] = self.baseMVA*(sol['z'][4::6] + complex(0.0,1.0)*sol['z'][5::6])

        # Generation
        sol['Sg'] = (matrix([gen['Pmin'] for gen in self.generators]) +\
                     matrix([0.0 if gen['pslack'] is None else sol['wpl'][gen['pslack']] for gen in self.generators])) +\
                     complex(0.0,1.0)*(matrix([gen['Qmin'] for gen in self.generators]) +\
                     matrix([0.0 if gen['qslack'] is None else sol['wql'][gen['qslack']] for gen in self.generators]))
        Pg = sol['Sg'].real()
        Qg = sol['Sg'].imag()
        for k,gen in enumerate(self.generators):
            gen['Pg'] = Pg[k]
            gen['Qg'] = Qg[k]
        sol['Sg'] *= self.baseMVA

        sol['cost'] = 0.0
        for ii,gen in enumerate(self.generators):
            for nk in range(gen['Pcost']['ncoef']):
                sol['cost'] += gen['Pcost']['coef'][-1-nk]*(Pg[ii]*self.baseMVA)**nk

        sol['cost_objective'] = -(self.problem_data[0].T*mu)[0]*self.cost_scale + self.const_cost

        sol['Vm'] = sqrt(matrix(sol['X'][::self.nbus+1]).real())
        return sol
예제 #23
0
파일: placement.py 프로젝트: cvxopt/cvxopt
if pylab_installed:
    # Figures for linear placement.

    pylab.figure(1, figsize=(10,4), facecolor='w')
    pylab.subplot(121) 
    X = matrix(0.0, (N+M,2))
    X[:N,:], X[N:,:] = X1, Xf
    pylab.plot(Xf[:,0], Xf[:,1], 'sw', mec = 'k')
    pylab.plot(X1[:,0], X1[:,1], 'or', ms=10)
    for s, t in E:  pylab.plot([X[s,0], X[t,0]], [X[s,1],X[t,1]], 'b:')
    pylab.axis([-1.1, 1.1, -1.1, 1.1])
    pylab.axis('equal')
    pylab.title('Linear placement')
    
    pylab.subplot(122) 
    lngths = sqrt((A1*X1 + B)**2 * matrix(1.0, (2,1)))
    pylab.hist(list(lngths), [.1*k for k in range(15)])
    x = pylab.arange(0, 1.6, 1.6/500)
    pylab.plot( x, 5.0/1.6*x, '--k')
    pylab.axis([0, 1.6, 0, 5.5])
    pylab.title('Length distribution')
    
    
    # Figures for quadratic placement.
    
    pylab.figure(2, figsize=(10,4), facecolor='w')
    pylab.subplot(121) 
    X[:N,:], X[N:,:] = X2, Xf
    pylab.plot(Xf[:,0], Xf[:,1], 'sw', mec = 'k')
    pylab.plot(X2[:,0], X2[:,1], 'or', ms=10)
    for s, t in E:  pylab.plot([X[s,0], X[t,0]], [X[s,1],X[t,1]], 'b:')
예제 #24
0
def Fkkt(W):
    """
        Custom solver:

          v := alpha * 2*A'*A * u + beta * v
    """

    global mmS
    mmS = matrix(0.0, (iR, iR))

    global vvV
    vvV = matrix(0.0, (iR, 1))

    # Factor
    #
    #     S = A*D^-1*A' + I
    #
    # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**2, D2 = d[n:]**2.
    mmAsc = matrix(0.0, (iR, iC))

    d1, d2 = W['di'][:iC]**2, W['di'][iC:]**2

    # ds is square root of diagonal of D
    ds = sqrt(2.0) * div(mul(W['di'][:iC], W['di'][iC:]), sqrt(d1 + d2))
    d3 = div(d2 - d1, d1 + d2)

    # Asc = A*diag(d)^-1/2
    blas.copy(mmTh, mmAsc)
    for k in range(iR):
        blas.tbsv(ds, mmAsc, n=iC, k=0, ldA=1, incx=iR, offsetx=k)

    # S = I + A * D^-1 * A'
    blas.syrk(mmAsc, mmS)
    mmS[::iR + 1] += 1.0
    lapack.potrf(mmS)

    def g(x, y, z):

        x[:iC] = 0.5 * ( x[:iC] - mul(d3, x[iC:]) + \
                mul(d1, z[:iC] + mul(d3, z[:iC])) - \
                mul(d2, z[iC:] - mul(d3, z[iC:])) )
        x[:iC] = div(x[:iC], ds)

        # Solve
        #
        #     S * v = 0.5 * A * D^-1 * ( bx[:n]
        #             - (D2-D1)*(D1+D2)^-1 * bx[n:]
        #             + D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bz[:n]
        #             - D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bz[n:] )

        blas.gemv(mmAsc, x, vvV)
        lapack.potrs(mmS, vvV)

        # x[:n] = D^-1 * ( rhs - A'*v ).
        blas.gemv(mmAsc, vvV, x, alpha=-1.0, beta=1.0, trans='T')
        x[:iC] = div(x[:iC], ds)

        # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bz[:n]  - D2*bz[n:] )
        #         - (D2-D1)*(D1+D2)^-1 * x[:n]
        x[iC:] = div( x[iC:] - mul(d1, z[:iC]) - mul(d2, z[iC:]), d1+d2 )\
                - mul( d3, x[:iC] )

        # z[:n] = D1^1/2 * (  x[:n] - x[n:] - bz[:n] )
        # z[n:] = D2^1/2 * ( -x[:n] - x[n:] - bz[n:] ).
        z[:iC] = mul(W['di'][:iC], x[:iC] - x[iC:] - z[:iC])
        z[iC:] = mul(W['di'][iC:], -x[:iC] - x[iC:] - z[iC:])

    return g
예제 #25
0
    def F(W): 
        """
        Custom solver for the system

        [  It  0   0    Xt'     0     At1' ...  Atk' ][ dwt  ]   [ rwt ]
        [  0   0   0    -d'     0      0   ...   0   ][ db   ]   [ rb  ]
        [  0   0   0    -I     -I      0   ...   0   ][ dv   ]   [ rv  ]
        [  Xt -d  -I  -Wl1^-2                        ][ dzl1 ]   [ rl1 ]
        [  0   0  -I         -Wl2^-2                 ][ dzl2 ] = [ rl2 ]
        [ At1  0   0                -W1^-2           ][ dz1  ]   [ r1  ] 
        [  |   |   |                       .         ][  |   ]   [  |  ]
        [ Atk  0   0                          -Wk^-2 ][ dzk  ]   [ rk  ]

        where

        It = [ I 0 ]  Xt = [ -D*X E ]  Ati = [ 0   -e_i' ]  
             [ 0 0 ]                         [ -Pi   0   ] 

        dwt = [ dw ]  rwt = [ rw ]
              [ dt ]        [ rt ].

        """

        # scalings and 'intermediate' vectors
        # db = inv(Wl1)^2 + inv(Wl2)^2
        db = W['di'][:m]**2 + W['di'][m:2*m]**2
        dbi = div(1.0,db)
        
        # dt = I - inv(Wl1)*Dbi*inv(Wl1)
        dt = 1.0 - mul(W['di'][:m]**2,dbi)
        dtsqrt = sqrt(dt)

        # lam = Dt*inv(Wl1)*d
        lam = mul(dt,mul(W['di'][:m],d))

        # lt = E'*inv(Wl1)*lam
        lt = matrix(0.0,(k,1))
        base.gemv(E, mul(W['di'][:m],lam), lt, trans = 'T')

        # Xs = sqrt(Dt)*inv(Wl1)*X
        tmp = mul(dtsqrt,W['di'][:m])
        Xs = spmatrix(tmp,range(m),range(m))*X

        # Es = D*sqrt(Dt)*inv(Wl1)*E
        Es = spmatrix(mul(d,tmp),range(m),range(m))*E

        # form Ab = I + sum((1/bi)^2*(Pi'*Pi + 4*(v'*v + 1)*Pi'*y*y'*Pi)) + Xs'*Xs
        #  and Bb = -sum((1/bi)^2*(4*ui*v'*v*Pi'*y*ei')) - Xs'*Es
        #  and D2 = Es'*Es + sum((1/bi)^2*(1+4*ui^2*(v'*v - 1))
        Ab = matrix(0.0,(n,n))
        Ab[::n+1] = 1.0
        base.syrk(Xs,Ab,trans = 'T', beta = 1.0)
        Bb = matrix(0.0,(n,k))
        Bb = -Xs.T*Es # inefficient!?
        D2 = spmatrix(0.0,range(k),range(k))
        base.syrk(Es,D2,trans = 'T', partial = True)
        d2 = +D2.V
        del D2
        py = matrix(0.0,(n,1))
        for i in range(k):
            binvsq = (1.0/W['beta'][i])**2
            Ab += binvsq*Pt[i]
            dvv = blas.dot(W['v'][i],W['v'][i])
            blas.gemv(P[i], W['v'][i][1:], py, trans = 'T', alpha = 1.0, beta = 0.0)
            blas.syrk(py, Ab, alpha = 4*binvsq*(dvv+1), beta = 1.0)
            Bb[:,i] -= 4*binvsq*W['v'][i][0]*dvv*py
            d2[i] += binvsq*(1+4*(W['v'][i][0]**2)*(dvv-1))
        
        d2i = div(1.0,d2)
        d2isqrt = sqrt(d2i)

        # compute a = alpha - lam'*inv(Wl1)*E*inv(D2)*E'*inv(Wl1)*lam
        alpha = blas.dot(lam,mul(W['di'][:m],d))
        tmp = matrix(0.0,(k,1))
        base.gemv(E,mul(W['di'][:m],lam), tmp, trans = 'T')
        tmp = mul(tmp, d2isqrt) #tmp = inv(D2)^(1/2)*E'*inv(Wl1)*lam
        a = alpha - blas.dot(tmp,tmp)

        # compute M12 = X'*D*inv(Wl1)*lam + Bb*inv(D2)*E'*inv(Wl1)*lam
        tmp = mul(tmp, d2isqrt)
        M12 = matrix(0.0,(n,1))
        blas.gemv(Bb,tmp,M12, alpha = 1.0)
        tmp = mul(d,mul(W['di'][:m],lam))
        blas.gemv(X,tmp,M12, trans = 'T', alpha = 1.0, beta = 1.0)

        # form and factor M
        sBb = Bb * spmatrix(d2isqrt,range(k), range(k)) 
        base.syrk(sBb, Ab, alpha = -1.0, beta = 1.0)
        M = matrix([[Ab, M12.T],[M12, a]])
        lapack.potrf(M)
        
        def f(x,y,z):
            
            # residuals
            rwt = x[:n+k]
            rb = x[n+k]
            rv = x[n+k+1:n+k+1+m]
            iw_rl1 = mul(W['di'][:m],z[:m])
            iw_rl2 = mul(W['di'][m:2*m],z[m:2*m])
            ri = [z[2*m+i*(n+1):2*m+(i+1)*(n+1)] for i in range(k)]
            
            # compute 'derived' residuals 
            # rbwt = rwt + sum(Ai'*inv(Wi)^2*ri) + [-X'*D; E']*inv(Wl1)^2*rl1
            rbwt = +rwt
            for i in range(k):
                tmp = +ri[i]
                qscal(tmp,W['beta'][i],W['v'][i],inv=True)
                qscal(tmp,W['beta'][i],W['v'][i],inv=True)
                rbwt[n+i] -= tmp[0]
                blas.gemv(P[i], tmp[1:], rbwt, trans = 'T', alpha = -1.0, beta = 1.0)
            tmp = mul(W['di'][:m],iw_rl1)
            tmp2 = matrix(0.0,(k,1))
            base.gemv(E,tmp,tmp2,trans='T')
            rbwt[n:] += tmp2
            tmp = mul(d,tmp) # tmp = D*inv(Wl1)^2*rl1
            blas.gemv(X,tmp,rbwt,trans='T', alpha = -1.0, beta = 1.0)
            
            # rbb = rb - d'*inv(Wl1)^2*rl1
            rbb = rb - sum(tmp)

            # rbv = rv - inv(Wl2)*rl2 - inv(Wl1)^2*rl1
            rbv = rv - mul(W['di'][m:2*m],iw_rl2) - mul(W['di'][:m],iw_rl1) 
            
            # [rtw;rtt] = rbwt + [-X'*D; E']*inv(Wl1)^2*inv(Db)*rbv 
            tmp = mul(W['di'][:m]**2, mul(dbi,rbv))
            rtt = +rbwt[n:] 
            base.gemv(E, tmp, rtt, trans = 'T', alpha = 1.0, beta = 1.0)
            rtw = +rbwt[:n]
            tmp = mul(d,tmp)
            blas.gemv(X, tmp, rtw, trans = 'T', alpha = -1.0, beta = 1.0)

            # rtb = rbb - d'*inv(Wl1)^2*inv(Db)*rbv
            rtb = rbb - sum(tmp)
            
            # solve M*[dw;db] = [rtw - Bb*inv(D2)*rtt; rtb + lt'*inv(D2)*rtt]
            tmp = mul(d2i,rtt)
            tmp2 = matrix(0.0,(n,1))
            blas.gemv(Bb,tmp,tmp2)
            dwdb = matrix([rtw - tmp2,rtb + blas.dot(mul(d2i,lt),rtt)]) 
            lapack.potrs(M,dwdb)

            # compute dt = inv(D2)*(rtt - Bb'*dw + lt*db)
            tmp2 = matrix(0.0,(k,1))
            blas.gemv(Bb, dwdb[:n], tmp2, trans='T')
            dt = mul(d2i, rtt - tmp2 + lt*dwdb[-1])

            # compute dv = inv(Db)*(rbv + inv(Wl1)^2*(E*dt - D*X*dw - d*db))
            dv = matrix(0.0,(m,1))
            blas.gemv(X,dwdb[:n],dv,alpha = -1.0)
            dv = mul(d,dv) - d*dwdb[-1]
            base.gemv(E, dt, dv, beta = 1.0)
            tmp = +dv  # tmp = E*dt - D*X*dw - d*db
            dv = mul(dbi, rbv + mul(W['di'][:m]**2,dv))

            # compute wdz1 = inv(Wl1)*(E*dt - D*X*dw - d*db - dv - rl1)
            wdz1 = mul(W['di'][:m], tmp - dv) - iw_rl1

            # compute wdz2 = - inv(Wl2)*(dv + rl2)
            wdz2 = - mul(W['di'][m:2*m],dv) - iw_rl2

            # compute wdzi = inv(Wi)*([-ei'*dt; -Pi*dw] - ri)
            wdzi = []
            tmp = matrix(0.0,(n,1))
            for i in range(k):
                blas.gemv(P[i],dwdb[:n],tmp, alpha = -1.0, beta = 0.0) 
                tmp1 = matrix([-dt[i],tmp])
                blas.axpy(ri[i],tmp1,alpha = -1.0)
                qscal(tmp1,W['beta'][i],W['v'][i],inv=True)
                wdzi.append(tmp1)

            # solution
            x[:n] = dwdb[:n]
            x[n:n+k] = dt
            x[n+k] = dwdb[-1]
            x[n+k+1:] = dv
            z[:m] = wdz1 
            z[m:2*m] = wdz2
            for i in range(k):
                z[2*m+i*(n+1):2*m+(i+1)*(n+1)] = wdzi[i]

        return f
예제 #26
0
    
    #INSERT CODE HERE TO MODIFY FEATURES
    # features is a n_examplesxn_features sparse matrix
    #binarize features
    print "Binarizing features"
    binarizer = preprocessing.Binarizer(threshold=0.0)
    
    binfeatures=binarizer.transform(features)
    #print binfeatures
    
    #cALCULATE DOT PRODUCT BETWEEN FEATURE REPRESENTATION OF EXAMPLES
    GMo=np.array(features.dot(features.T).todense())
    #normalize GM matrix
    GMo=co.matrix(GMo)
    YY = co.matrix([GMo[i,i] for i in range(GMo.size[0])])
    YY = co.sqrt(YY)**(-1)
    GMo = co.mul(GMo, YY*YY.T)
    #print GMo

    # START MIRKO
    print "Calculating D-kernel..."
    R = co.matrix(binfeatures.todense())
    K = d_kernel(R, d)
    #GM = np.array(K)+ GMo#.tolist()
    GM = K+ GMo#.tolist()

    #GM=co.matrix(GM)
    YY = co.matrix([GM[i,i] for i in range(GM.size[0])])
    YY = co.sqrt(YY)**(-1)
    GM = np.array(co.mul(GM, YY*YY.T))
    # END MIRKO
예제 #27
0
def proxqp_clique_SNL(c, A, b, z, rho):
    """
    Solves the 1-norm regularized conic LP

        min.  < c, x > + || A(x) - b ||_1 + (rho/2) || x - z ||^2
        s.t.  x >= 0

    for a single dense clique .
    
    The method is used in this package to solve the 
    sensor node localization problem
    
    Input arguments.

        c is a 'd' matrix of size n_k**2 x 1

        A is a 'd' matrix.  with size n_k**2 times m_k.  Each of its columns 
            represents a symmetric matrix of order n_k in unpacked column-major 
            order. The term  A ( x ) in the primal constraint is given by

                A(x) = A' * vec(x).

            The adjoint A'( y ) in the dual constraint is given by

                A'(y) = mat( A * y ).

            Only the entries of A corresponding to lower-triangular
            positions are accessed.
             

        b is a 'd' matrix of size m_k x 1.

        z is a 'd' matrix of size n_k**2 x 1
        
        rho is a positive scalar.  


    Output arguments.

        sol : Solution dictionary for quadratic optimization problem.
        
        primal : objective for optimization problem without prox term (trace C*X)

    """

    ns2, ms = A.size
    nl, msl = len(b) * 2, len(b)

    ns = int(sqrt(ns2))
    dims = {'l': nl, 'q': [], 's': [ns]}

    c = matrix([matrix(1.0, (nl, 1)), c])
    z = matrix([matrix(0.0, (nl, 1)), z])
    q = +c
    blas.axpy(z, q, alpha=-rho, offsetx=nl, offsety=nl)

    symmetrize(q, ns, offset=nl)
    q = q[:]
    h = matrix(0.0, (nl + ns2, 1))

    bz = +q
    xp = +q

    def P(u, v, alpha=1.0, beta=0.0):
        # v := alpha * rho * u + beta * v
        blas.scal(beta, v)
        blas.axpy(u, v, alpha=alpha * rho, offsetx=nl, offsety=nl)

    def xdot(x, y):
        misc.trisc(x, dims)
        adot = blas.dot(x, y)
        misc.triusc(x, dims)
        return adot

    def Gf(u, v, alpha=1.0, beta=0.0, trans='N'):
        # v = -alpha*u + beta * v
        blas.scal(beta, v)
        blas.axpy(u, v, alpha=-alpha)

    def Af(u, v, alpha=1.0, beta=0.0, trans="N"):

        # v := alpha * A(u) + beta * v if trans is 'N'
        # v := alpha * A'(u) + beta * v if trans is 'T'
        blas.scal(beta, v)
        if trans == "N":
            blas.axpy(u, v, alpha=alpha, n=nl / 2)
            blas.axpy(u, v, alpha=-alpha, offsetx=nl / 2, n=nl / 2)
            sgemv(A,
                  u,
                  v,
                  n=ns,
                  m=ms,
                  alpha=alpha,
                  beta=1.0,
                  trans="T",
                  offsetx=nl)

        elif trans == "T":
            blas.axpy(u, v, alpha=alpha, n=nl / 2)
            blas.axpy(u, v, alpha=-alpha, offsety=nl / 2, n=nl / 2)
            sgemv(A,
                  u,
                  v,
                  n=ns,
                  m=ms,
                  alpha=alpha,
                  beta=1.0,
                  trans="N",
                  offsety=nl)

    U = matrix(0.0, (ns, ns))
    Vt = matrix(0.0, (ns, ns))
    sv = matrix(0.0, (ns, 1))
    Gamma = matrix(0.0, (ns, ns))

    if type(A) is spmatrix:
        VecAIndex = +A[:].I
    As = matrix(A)
    Aspkd = matrix(0.0, ((ns + 1) * ns / 2, ms))
    tmp = matrix(0.0, (ms, 1))

    def F(W):
        # SVD R[j] = U[j] * diag(sig[j]) * Vt[j]
        lapack.gesvd(+W['r'][0], sv, jobu='A', jobvt='A', U=U, Vt=Vt)

        W2 = mul(+W['d'], +W['d'])

        # Vt[j] := diag(sig[j])^-1 * Vt[j]
        for k in xrange(ns):
            blas.tbsv(sv, Vt, n=ns, k=0, ldA=1, offsetx=k * ns)

        # Gamma[j] is an ns[j] x ns[j] symmetric matrix
        #  (sig[j] * sig[j]') ./  sqrt(1 + rho * (sig[j] * sig[j]').^2)
        # S = sig[j] * sig[j]'
        S = matrix(0.0, (ns, ns))
        blas.syrk(sv, S)
        Gamma = div(S, sqrt(1.0 + rho * S**2))
        symmetrize(Gamma, ns)

        # As represents the scaled mapping
        #
        #     As(x) = A(u * (Gamma .* x) * u')
        #    As'(y) = Gamma .* (u' * A'(y) * u)
        #
        # stored in a similar format as A, except that we use packed
        # storage for the columns of As[i][j].

        if type(A) is spmatrix:
            blas.scal(0.0, As)
            As[VecAIndex] = +A[VecAIndex]
        else:
            blas.copy(A, As)

        # As[i][j][:,k] = diag( diag(Gamma[j]))*As[i][j][:,k]
        # As[i][j][l,:] = Gamma[j][l,l]*As[i][j][l,:]
        for k in xrange(ms):
            cngrnc(U, As, trans='T', offsetx=k * (ns2))
            blas.tbmv(Gamma, As, n=ns2, k=0, ldA=1, offsetx=k * (ns2))

        misc.pack(As, Aspkd, {'l': 0, 'q': [], 's': [ns] * ms})

        # H is an m times m block matrix with i, k block
        #
        #      Hik = sum_j As[i,j]' * As[k,j]
        #
        # of size ms[i] x ms[k].  Hik = 0 if As[i,j] or As[k,j]
        # are zero for all j
        H = matrix(0.0, (ms, ms))
        blas.syrk(Aspkd, H, trans='T', beta=1.0, k=ns * (ns + 1) / 2)

        #H = H + spmatrix(W2[:nl/2] + W2[nl/2:] ,range(nl/2),range(nl/2))
        blas.axpy(W2, H, n=ms, incy=ms + 1, alpha=1.0)
        blas.axpy(W2, H, offsetx=ms, n=ms, incy=ms + 1, alpha=1.0)

        lapack.potrf(H)

        def solve(x, y, z):
            """
            Returns solution of 

                rho * ux + A'(uy) - r^-T * uz * r^-1 = bx
                A(ux)                                = by
                -ux               - r * uz * r'      = bz.

            On entry, x = bx, y = by, z = bz.
            On exit, x = ux, y = uy, z = uz.
            """

            # bz is a copy of z in the format of x
            blas.copy(z, bz)
            blas.axpy(bz, x, alpha=rho, offsetx=nl, offsety=nl)
            # x := Gamma .* (u' * x * u)
            #    = Gamma .* (u' * (bx + rho * bz) * u)

            cngrnc(U, x, trans='T', offsetx=nl)
            blas.tbmv(Gamma, x, n=ns2, k=0, ldA=1, offsetx=nl)
            blas.tbmv(+W['d'], x, n=nl, k=0, ldA=1)

            # y := y - As(x)
            #   := by - As( Gamma .* u' * (bx + rho * bz) * u)

            misc.pack(x, xp, dims)
            blas.gemv(Aspkd, xp, y, trans = 'T',alpha = -1.0, beta = 1.0, \
                m = ns*(ns+1)/2, n = ms,offsetx = nl)

            #y = y - mul(+W['d'][:nl/2],xp[:nl/2])+ mul(+W['d'][nl/2:nl],xp[nl/2:nl])
            blas.tbmv(+W['d'], xp, n=nl, k=0, ldA=1)
            blas.axpy(xp, y, alpha=-1, n=ms)
            blas.axpy(xp, y, alpha=1, n=ms, offsetx=nl / 2)

            # y := -y - A(bz)
            #    = -by - A(bz) + As(Gamma .*  (u' * (bx + rho * bz) * u)

            Af(bz, y, alpha=-1.0, beta=-1.0)

            # y := H^-1 * y
            #    = H^-1 ( -by - A(bz) + As(Gamma.* u'*(bx + rho*bz)*u) )
            #    = uy

            blas.trsv(H, y)
            blas.trsv(H, y, trans='T')

            # bz = Vt' * vz * Vt
            #    = uz where
            # vz := Gamma .* ( As'(uy)  - x )
            #     = Gamma .* ( As'(uy)  - Gamma .* (u'*(bx + rho *bz)*u) )
            #     = Gamma.^2 .* ( u' * (A'(uy) - bx - rho * bz) * u ).

            misc.pack(x, xp, dims)
            blas.scal(-1.0, xp)

            blas.gemv(Aspkd,
                      y,
                      xp,
                      alpha=1.0,
                      beta=1.0,
                      m=ns * (ns + 1) / 2,
                      n=ms,
                      offsety=nl)

            #xp[:nl/2] = xp[:nl/2] + mul(+W['d'][:nl/2],y)
            #xp[nl/2:nl] = xp[nl/2:nl] - mul(+W['d'][nl/2:nl],y)

            blas.copy(y, tmp)
            blas.tbmv(+W['d'], tmp, n=nl / 2, k=0, ldA=1)
            blas.axpy(tmp, xp, n=nl / 2)

            blas.copy(y, tmp)
            blas.tbmv(+W['d'], tmp, n=nl / 2, k=0, ldA=1, offsetA=nl / 2)
            blas.axpy(tmp, xp, alpha=-1, n=nl / 2, offsety=nl / 2)

            # bz[j] is xp unpacked and multiplied with Gamma
            blas.copy(xp, bz)  #,n = nl)
            misc.unpack(xp, bz, dims)
            blas.tbmv(Gamma, bz, n=ns2, k=0, ldA=1, offsetx=nl)

            # bz = Vt' * bz * Vt
            #    = uz
            cngrnc(Vt, bz, trans='T', offsetx=nl)

            symmetrize(bz, ns, offset=nl)

            # x = -bz - r * uz * r'
            # z contains r.h.s. bz;  copy to x
            #so far, z = bzc (untouched)
            blas.copy(z, x)
            blas.copy(bz, z)

            cngrnc(W['r'][0], bz, offsetx=nl)
            blas.tbmv(W['d'], bz, n=nl, k=0, ldA=1)

            blas.axpy(bz, x)
            blas.scal(-1.0, x)

        return solve

    sol = solvers.coneqp(P, q, Gf, h, dims, Af, b, None, F, xdot=xdot)
    primal = blas.dot(sol['s'], c)

    sol['s'] = sol['s'][nl:]
    sol['z'] = sol['z'][nl:]

    return sol, primal
예제 #28
0
def mrcompletion(A, reordered=True):
    """
    Minimum rank positive semidefinite completion. The routine takes a 
    positive semidefinite cspmatrix :math:`A` and returns a dense
    matrix :math:`Y` with :math:`r` columns that satisfies

    .. math::
         P( YY^T ) = A

    where 

    .. math::
         r = \max_{i} |\gamma_i|

    is the clique number (the size of the largest clique).
    
    :param A:                 :py:class:`cspmatrix`
    :param reordered:         boolean
    """

    assert isinstance(A, cspmatrix) and A.is_factor is False, "A must be a cspmatrix"

    symb = A.symb
    n = symb.n
    
    snpost = symb.snpost
    snptr = symb.snptr
    chptr = symb.chptr
    chidx = symb.chidx

    relptr = symb.relptr
    relidx = symb.relidx
    blkptr = symb.blkptr
    blkval = A.blkval

    stack = []
    r = 0 

    maxr = symb.clique_number
    Y = matrix(0.0,(n,maxr))       # storage for factorization
    Z = matrix(0.0,(maxr,maxr))    # storage for EVD of cliques
    w = matrix(0.0,(maxr,1))       # storage for EVD of cliques

    P = matrix(0.0,(maxr,maxr))    # storage for left singular vectors
    Q1t = matrix(0.0,(maxr,maxr))  # storage for right singular vectors (1)
    Q2t = matrix(0.0,(maxr,maxr))  # storage for right singular vectors (2)
    S = matrix(0.0,(maxr,1))       # storage for singular values

    V = matrix(0.0,(maxr,maxr))
    Ya = matrix(0.0,(maxr,maxr))
    
    # visit supernodes in reverse topological order
    for k in range(symb.Nsn-1,-1,-1):

        nn = snptr[k+1]-snptr[k]       # |Nk|
        na = relptr[k+1]-relptr[k]     # |Ak|
        nj = na + nn

        # allocate F and copy X_{Jk,Nk} to leading columns of F
        F = matrix(0.0, (nj,nj))
        lapack.lacpy(blkval, F, offsetA = blkptr[k], ldA = nj, m = nj, n = nn, uplo = 'L')

        # if supernode k is not a root node:
        if na > 0:
            # copy Vk to 2,2 block of F
            Vk = stack.pop()
            lapack.lacpy(Vk, F, offsetB = nn*nj+nn, m = na, n = na, uplo = 'L')

        # if supernode k has any children:
        for ii in range(chptr[k],chptr[k+1]):
            stack.append(frontal_get_update(F,relidx,relptr,chidx[ii]))

        # Compute factorization of F
        lapack.syevr(F, w, jobz='V', range='A', uplo='L', Z=Z, n=nj,ldZ=maxr)
        rk = sum([1 for wi in w[:nj] if wi > 1e-14*w[nj-1]])  # determine rank of clique k
        r = max(rk,r)                                         # update rank
        
        # Scale last rk cols of Z and copy parts to Yn
        for j in range(nj-rk,nj):
            Z[:nj,j] *= sqrt(w[j])
        In = symb.snrowidx[symb.sncolptr[k]:symb.sncolptr[k]+nn]
        Y[In,:rk] = Z[:nn,nj-rk:nj]

        # if supernode k is not a root node:
        if na > 0:
            # Extract data
            Ia = symb.snrowidx[symb.sncolptr[k]+nn:symb.sncolptr[k+1]]
            Ya[:na,:r] = Y[Ia,:r]
            V[:na,:rk] = Z[nn:nj,nj-rk:nj]
            V[:na,rk:r] *= 0.0            
            # Compute SVDs: V = P*S*Q1t and Ya = P*S*Q2t
            lapack.gesvd(V,S,jobu='A',jobvt='A',U=P,Vt=Q1t,ldU=maxr,ldVt=maxr,m=na,n=r,ldA=maxr)
            lapack.gesvd(Ya,S,jobu='N',jobvt='A',Vt=Q2t,ldVt=maxr,m=na,n=r,ldA=maxr)
            # Scale Q2t 
            for i in range(min(na,rk)):
                if S[i] > 1e-14*S[0]: Q2t[i,:r] = P[:na,i].T*Y[Ia,:r]/S[i]
            # Scale Yn            
            Y[In,:r] = Y[In,:r]*Q1t[:r,:r].T*Q2t[:r,:r]
                        
    if reordered:
        return Y[:,:r]
    else:
        return Y[symb.ip,:r]
예제 #29
0
def proxqp_clique(c, A, b, z, rho):
    """
    Solves the conic QP

        min.  < c, x > + (rho/2) || x - z ||^2
        s.t.  A(x) = b
              x >= 0

    and its dual

        max.  -< b, y > - 1/(2*rho) * || c + A'(y) - rho * z - s ||^2 
        s.t.  s >= 0.

    for a single dense clique. 
    
    If the problem has block-arrow correlative sparsity, then the previous
    function 
    
    X = proxqp(c,A,b,z,rho,**kwargs)
    
    is equivalent to
    
    for k in xrange(ncliques):
        X[k] = proxqp_clique(c[k],A[k][k],b[k],z[k],rho,**kwargs)
    
    and each call can be implemented in parallel.
    
    Input arguments.

        c is a 'd' matrix of size n_k**2 x 1

        A is a 'd' matrix.  with size n_k**2 times m_k.  Each of its columns 
            represents a symmetric matrix of order n_k in unpacked column-major 
            order. The term  A ( x ) in the primal constraint is given by

                A(x) = A' * vec(x).

            The adjoint A'( y ) in the dual constraint is given by

                A'(y) = mat( A * y ).
             

        b is a 'd' matrix of size m_k x 1.
        
        z is a 'd' matrix of size n_k**2 x 1
        
        rho is a positive scalar.  

    Output arguments.
    
        sol : Solution dictionary for quadratic optimization problem.
        
        primal : objective for optimization problem without prox term (trace C*X)

    """

    ns2, ms = A.size
    ns = int(sqrt(ns2))
    dims = {'l': 0, 'q': [], 's': [ns]}

    q = +c
    blas.axpy(z, q, alpha=-rho)
    symmetrize(q, ns, offset=0)
    q = q[:]
    h = matrix(0.0, (ns2, 1))

    bz = +q
    xp = +q

    def P(u, v, alpha=1.0, beta=0.0):
        # v := alpha * rho * u + beta * v
        #if not (beta==0.0):
        blas.scal(beta, v)
        blas.axpy(u, v, alpha=alpha * rho)

    def xdot(x, y):
        misc.trisc(x, {'l': 0, 'q': [], 's': [ns]})
        adot = blas.dot(x, y)
        misc.triusc(x, {'l': 0, 'q': [], 's': [ns]})
        return adot

    def Gf(u, v, alpha=1.0, beta=0.0, trans='N'):

        # v = -alpha*u + beta * v
        # u and v are vectors representing N symmetric matrices in the
        # cvxopt format.
        blas.scal(beta, v)
        blas.axpy(u, v, alpha=-alpha)

    def Af(u, v, alpha=1.0, beta=0.0, trans="N"):

        # v := alpha * A(u) + beta * v if trans is 'N'
        # v := alpha * A'(u) + beta * v if trans is 'T'
        blas.scal(beta, v)
        if trans == "N":
            sgemv(A,
                  u,
                  v,
                  n=ns,
                  m=ms,
                  alpha=alpha,
                  beta=1.0,
                  trans="T",
                  offsetx=0)
        elif trans == "T":
            sgemv(A,
                  u,
                  v,
                  n=ns,
                  m=ms,
                  alpha=alpha,
                  beta=1.0,
                  trans="N",
                  offsetx=0)

    U = matrix(0.0, (ns, ns))
    Vt = matrix(0.0, (ns, ns))
    sv = matrix(0.0, (ns, 1))
    Gamma = matrix(0.0, (ns, ns))

    if type(A) is spmatrix:
        VecAIndex = +A[:].I

    Aspkd = matrix(0.0, ((ns + 1) * ns / 2, ms))
    As = matrix(A)

    def F(W):
        # SVD R[j] = U[j] * diag(sig[j]) * Vt[j]
        lapack.gesvd(+W['r'][0], sv, jobu='A', jobvt='A', U=U, Vt=Vt)

        # Vt[j] := diag(sig[j])^-1 * Vt[j]
        for k in xrange(ns):
            blas.tbsv(sv, Vt, n=ns, k=0, ldA=1, offsetx=k * ns)

        # Gamma[j] is an ns[j] x ns[j] symmetric matrix
        #
        #  (sig[j] * sig[j]') ./  sqrt(1 + rho * (sig[j] * sig[j]').^2)

        # S = sig[j] * sig[j]'
        S = matrix(0.0, (ns, ns))
        blas.syrk(sv, S)
        Gamma = div(S, sqrt(1.0 + rho * S**2))
        symmetrize(Gamma, ns)

        # As represents the scaled mapping
        #
        #     As(x) = A(u * (Gamma .* x) * u')
        #    As'(y) = Gamma .* (u' * A'(y) * u)
        #
        # stored in a similar format as A, except that we use packed
        # storage for the columns of As[i][j].

        if type(A) is spmatrix:
            blas.scal(0.0, As)
            try:
                As[VecAIndex] = +A['s'][VecAIndex]
            except:
                As[VecAIndex] = +A[VecAIndex]
        else:
            blas.copy(A, As)

        # As[i][j][:,k] = diag( diag(Gamma[j]))*As[i][j][:,k]
        # As[i][j][l,:] = Gamma[j][l,l]*As[i][j][l,:]
        for k in xrange(ms):
            cngrnc(U, As, trans='T', offsetx=k * (ns2))
            blas.tbmv(Gamma, As, n=ns2, k=0, ldA=1, offsetx=k * (ns2))

        misc.pack(As, Aspkd, {'l': 0, 'q': [], 's': [ns] * ms})

        # H is an m times m block matrix with i, k block
        #
        #      Hik = sum_j As[i,j]' * As[k,j]
        #
        # of size ms[i] x ms[k].  Hik = 0 if As[i,j] or As[k,j]
        # are zero for all j
        H = matrix(0.0, (ms, ms))
        blas.syrk(Aspkd, H, trans='T', beta=1.0, k=ns * (ns + 1) / 2)

        lapack.potrf(H)

        def solve(x, y, z):
            """
            Returns solution of 

                rho * ux + A'(uy) - r^-T * uz * r^-1 = bx
                A(ux)                                = by
                -ux               - r * uz * r'      = bz.

            On entry, x = bx, y = by, z = bz.
            On exit, x = ux, y = uy, z = uz.
            """

            # bz is a copy of z in the format of x
            blas.copy(z, bz)
            blas.axpy(bz, x, alpha=rho)

            # x := Gamma .* (u' * x * u)
            #    = Gamma .* (u' * (bx + rho * bz) * u)

            cngrnc(U, x, trans='T', offsetx=0)
            blas.tbmv(Gamma, x, n=ns2, k=0, ldA=1, offsetx=0)

            # y := y - As(x)
            #   := by - As( Gamma .* u' * (bx + rho * bz) * u)
            #blas.copy(x,xp)
            #pack_ip(xp,n = ns,m=1,nl=nl)
            misc.pack(x, xp, {'l': 0, 'q': [], 's': [ns]})

            blas.gemv(Aspkd, xp, y, trans = 'T',alpha = -1.0, beta = 1.0, \
                m = ns*(ns+1)/2, n = ms,offsetx = 0)

            # y := -y - A(bz)
            #    = -by - A(bz) + As(Gamma .*  (u' * (bx + rho * bz) * u)
            Af(bz, y, alpha=-1.0, beta=-1.0)

            # y := H^-1 * y
            #    = H^-1 ( -by - A(bz) + As(Gamma.* u'*(bx + rho*bz)*u) )
            #    = uy

            blas.trsv(H, y)
            blas.trsv(H, y, trans='T')

            # bz = Vt' * vz * Vt
            #    = uz where
            # vz := Gamma .* ( As'(uy)  - x )
            #     = Gamma .* ( As'(uy)  - Gamma .* (u'*(bx + rho *bz)*u) )
            #     = Gamma.^2 .* ( u' * (A'(uy) - bx - rho * bz) * u ).
            #blas.copy(x,xp)
            #pack_ip(xp,n=ns,m=1,nl=nl)

            misc.pack(x, xp, {'l': 0, 'q': [], 's': [ns]})
            blas.scal(-1.0, xp)

            blas.gemv(Aspkd,
                      y,
                      xp,
                      alpha=1.0,
                      beta=1.0,
                      m=ns * (ns + 1) / 2,
                      n=ms,
                      offsety=0)

            # bz[j] is xp unpacked and multiplied with Gamma
            misc.unpack(xp, bz, {'l': 0, 'q': [], 's': [ns]})
            blas.tbmv(Gamma, bz, n=ns2, k=0, ldA=1, offsetx=0)

            # bz = Vt' * bz * Vt
            #    = uz
            cngrnc(Vt, bz, trans='T', offsetx=0)

            symmetrize(bz, ns, offset=0)

            # x = -bz - r * uz * r'
            # z contains r.h.s. bz;  copy to x
            blas.copy(z, x)
            blas.copy(bz, z)

            cngrnc(W['r'][0], bz, offsetx=0)
            blas.axpy(bz, x)
            blas.scal(-1.0, x)

        return solve

    #solvers.options['show_progress'] = True
    sol = solvers.coneqp(P, q, Gf, h, dims, Af, b, None, F, xdot=xdot)
    primal = blas.dot(c, sol['s'])
    return sol, primal
예제 #30
0
파일: robsvm.py 프로젝트: rubiruchi/sim_rel
    def F(W):
        """
        Custom solver for the system

        [  It  0   0    Xt'     0     At1' ...  Atk' ][ dwt  ]   [ rwt ]
        [  0   0   0    -d'     0      0   ...   0   ][ db   ]   [ rb  ]
        [  0   0   0    -I     -I      0   ...   0   ][ dv   ]   [ rv  ]
        [  Xt -d  -I  -Wl1^-2                        ][ dzl1 ]   [ rl1 ]
        [  0   0  -I         -Wl2^-2                 ][ dzl2 ] = [ rl2 ]
        [ At1  0   0                -W1^-2           ][ dz1  ]   [ r1  ] 
        [  |   |   |                       .         ][  |   ]   [  |  ]
        [ Atk  0   0                          -Wk^-2 ][ dzk  ]   [ rk  ]

        where

        It = [ I 0 ]  Xt = [ -D*X E ]  Ati = [ 0   -e_i' ]  
             [ 0 0 ]                         [ -Pi   0   ] 

        dwt = [ dw ]  rwt = [ rw ]
              [ dt ]        [ rt ].

        """

        # scalings and 'intermediate' vectors
        # db = inv(Wl1)^2 + inv(Wl2)^2
        db = W['di'][:m]**2 + W['di'][m:2 * m]**2
        dbi = div(1.0, db)

        # dt = I - inv(Wl1)*Dbi*inv(Wl1)
        dt = 1.0 - mul(W['di'][:m]**2, dbi)
        dtsqrt = sqrt(dt)

        # lam = Dt*inv(Wl1)*d
        lam = mul(dt, mul(W['di'][:m], d))

        # lt = E'*inv(Wl1)*lam
        lt = matrix(0.0, (k, 1))
        base.gemv(E, mul(W['di'][:m], lam), lt, trans='T')

        # Xs = sqrt(Dt)*inv(Wl1)*X
        tmp = mul(dtsqrt, W['di'][:m])
        Xs = spmatrix(tmp, range(m), range(m)) * X

        # Es = D*sqrt(Dt)*inv(Wl1)*E
        Es = spmatrix(mul(d, tmp), range(m), range(m)) * E

        # form Ab = I + sum((1/bi)^2*(Pi'*Pi + 4*(v'*v + 1)*Pi'*y*y'*Pi)) + Xs'*Xs
        #  and Bb = -sum((1/bi)^2*(4*ui*v'*v*Pi'*y*ei')) - Xs'*Es
        #  and D2 = Es'*Es + sum((1/bi)^2*(1+4*ui^2*(v'*v - 1))
        Ab = matrix(0.0, (n, n))
        Ab[::n + 1] = 1.0
        base.syrk(Xs, Ab, trans='T', beta=1.0)
        Bb = matrix(0.0, (n, k))
        Bb = -Xs.T * Es  # inefficient!?
        D2 = spmatrix(0.0, range(k), range(k))
        base.syrk(Es, D2, trans='T', partial=True)
        d2 = +D2.V
        del D2
        py = matrix(0.0, (n, 1))
        for i in range(k):
            binvsq = (1.0 / W['beta'][i])**2
            Ab += binvsq * Pt[i]
            dvv = blas.dot(W['v'][i], W['v'][i])
            blas.gemv(P[i], W['v'][i][1:], py, trans='T', alpha=1.0, beta=0.0)
            blas.syrk(py, Ab, alpha=4 * binvsq * (dvv + 1), beta=1.0)
            Bb[:, i] -= 4 * binvsq * W['v'][i][0] * dvv * py
            d2[i] += binvsq * (1 + 4 * (W['v'][i][0]**2) * (dvv - 1))

        d2i = div(1.0, d2)
        d2isqrt = sqrt(d2i)

        # compute a = alpha - lam'*inv(Wl1)*E*inv(D2)*E'*inv(Wl1)*lam
        alpha = blas.dot(lam, mul(W['di'][:m], d))
        tmp = matrix(0.0, (k, 1))
        base.gemv(E, mul(W['di'][:m], lam), tmp, trans='T')
        tmp = mul(tmp, d2isqrt)  #tmp = inv(D2)^(1/2)*E'*inv(Wl1)*lam
        a = alpha - blas.dot(tmp, tmp)

        # compute M12 = X'*D*inv(Wl1)*lam + Bb*inv(D2)*E'*inv(Wl1)*lam
        tmp = mul(tmp, d2isqrt)
        M12 = matrix(0.0, (n, 1))
        blas.gemv(Bb, tmp, M12, alpha=1.0)
        tmp = mul(d, mul(W['di'][:m], lam))
        blas.gemv(X, tmp, M12, trans='T', alpha=1.0, beta=1.0)

        # form and factor M
        sBb = Bb * spmatrix(d2isqrt, range(k), range(k))
        base.syrk(sBb, Ab, alpha=-1.0, beta=1.0)
        M = matrix([[Ab, M12.T], [M12, a]])
        lapack.potrf(M)

        def f(x, y, z):

            # residuals
            rwt = x[:n + k]
            rb = x[n + k]
            rv = x[n + k + 1:n + k + 1 + m]
            iw_rl1 = mul(W['di'][:m], z[:m])
            iw_rl2 = mul(W['di'][m:2 * m], z[m:2 * m])
            ri = [
                z[2 * m + i * (n + 1):2 * m + (i + 1) * (n + 1)]
                for i in range(k)
            ]

            # compute 'derived' residuals
            # rbwt = rwt + sum(Ai'*inv(Wi)^2*ri) + [-X'*D; E']*inv(Wl1)^2*rl1
            rbwt = +rwt
            for i in range(k):
                tmp = +ri[i]
                qscal(tmp, W['beta'][i], W['v'][i], inv=True)
                qscal(tmp, W['beta'][i], W['v'][i], inv=True)
                rbwt[n + i] -= tmp[0]
                blas.gemv(P[i], tmp[1:], rbwt, trans='T', alpha=-1.0, beta=1.0)
            tmp = mul(W['di'][:m], iw_rl1)
            tmp2 = matrix(0.0, (k, 1))
            base.gemv(E, tmp, tmp2, trans='T')
            rbwt[n:] += tmp2
            tmp = mul(d, tmp)  # tmp = D*inv(Wl1)^2*rl1
            blas.gemv(X, tmp, rbwt, trans='T', alpha=-1.0, beta=1.0)

            # rbb = rb - d'*inv(Wl1)^2*rl1
            rbb = rb - sum(tmp)

            # rbv = rv - inv(Wl2)*rl2 - inv(Wl1)^2*rl1
            rbv = rv - mul(W['di'][m:2 * m], iw_rl2) - mul(W['di'][:m], iw_rl1)

            # [rtw;rtt] = rbwt + [-X'*D; E']*inv(Wl1)^2*inv(Db)*rbv
            tmp = mul(W['di'][:m]**2, mul(dbi, rbv))
            rtt = +rbwt[n:]
            base.gemv(E, tmp, rtt, trans='T', alpha=1.0, beta=1.0)
            rtw = +rbwt[:n]
            tmp = mul(d, tmp)
            blas.gemv(X, tmp, rtw, trans='T', alpha=-1.0, beta=1.0)

            # rtb = rbb - d'*inv(Wl1)^2*inv(Db)*rbv
            rtb = rbb - sum(tmp)

            # solve M*[dw;db] = [rtw - Bb*inv(D2)*rtt; rtb + lt'*inv(D2)*rtt]
            tmp = mul(d2i, rtt)
            tmp2 = matrix(0.0, (n, 1))
            blas.gemv(Bb, tmp, tmp2)
            dwdb = matrix([rtw - tmp2, rtb + blas.dot(mul(d2i, lt), rtt)])
            lapack.potrs(M, dwdb)

            # compute dt = inv(D2)*(rtt - Bb'*dw + lt*db)
            tmp2 = matrix(0.0, (k, 1))
            blas.gemv(Bb, dwdb[:n], tmp2, trans='T')
            dt = mul(d2i, rtt - tmp2 + lt * dwdb[-1])

            # compute dv = inv(Db)*(rbv + inv(Wl1)^2*(E*dt - D*X*dw - d*db))
            dv = matrix(0.0, (m, 1))
            blas.gemv(X, dwdb[:n], dv, alpha=-1.0)
            dv = mul(d, dv) - d * dwdb[-1]
            base.gemv(E, dt, dv, beta=1.0)
            tmp = +dv  # tmp = E*dt - D*X*dw - d*db
            dv = mul(dbi, rbv + mul(W['di'][:m]**2, dv))

            # compute wdz1 = inv(Wl1)*(E*dt - D*X*dw - d*db - dv - rl1)
            wdz1 = mul(W['di'][:m], tmp - dv) - iw_rl1

            # compute wdz2 = - inv(Wl2)*(dv + rl2)
            wdz2 = -mul(W['di'][m:2 * m], dv) - iw_rl2

            # compute wdzi = inv(Wi)*([-ei'*dt; -Pi*dw] - ri)
            wdzi = []
            tmp = matrix(0.0, (n, 1))
            for i in range(k):
                blas.gemv(P[i], dwdb[:n], tmp, alpha=-1.0, beta=0.0)
                tmp1 = matrix([-dt[i], tmp])
                blas.axpy(ri[i], tmp1, alpha=-1.0)
                qscal(tmp1, W['beta'][i], W['v'][i], inv=True)
                wdzi.append(tmp1)

            # solution
            x[:n] = dwdb[:n]
            x[n:n + k] = dt
            x[n + k] = dwdb[-1]
            x[n + k + 1:] = dv
            z[:m] = wdz1
            z[m:2 * m] = wdz2
            for i in range(k):
                z[2 * m + i * (n + 1):2 * m + (i + 1) * (n + 1)] = wdzi[i]

        return f
예제 #31
0
    def F(W):
        # SVD R[j] = U[j] * diag(sig[j]) * Vt[j]
        lapack.gesvd(+W['r'][0], sv, jobu='A', jobvt='A', U=U, Vt=Vt)

        # Vt[j] := diag(sig[j])^-1 * Vt[j]
        for k in xrange(ns):
            blas.tbsv(sv, Vt, n=ns, k=0, ldA=1, offsetx=k * ns)

        # Gamma[j] is an ns[j] x ns[j] symmetric matrix
        #
        #  (sig[j] * sig[j]') ./  sqrt(1 + rho * (sig[j] * sig[j]').^2)

        # S = sig[j] * sig[j]'
        S = matrix(0.0, (ns, ns))
        blas.syrk(sv, S)
        Gamma = div(S, sqrt(1.0 + rho * S**2))
        symmetrize(Gamma, ns)

        # As represents the scaled mapping
        #
        #     As(x) = A(u * (Gamma .* x) * u')
        #    As'(y) = Gamma .* (u' * A'(y) * u)
        #
        # stored in a similar format as A, except that we use packed
        # storage for the columns of As[i][j].

        if type(A) is spmatrix:
            blas.scal(0.0, As)
            try:
                As[VecAIndex] = +A['s'][VecAIndex]
            except:
                As[VecAIndex] = +A[VecAIndex]
        else:
            blas.copy(A, As)

        # As[i][j][:,k] = diag( diag(Gamma[j]))*As[i][j][:,k]
        # As[i][j][l,:] = Gamma[j][l,l]*As[i][j][l,:]
        for k in xrange(ms):
            cngrnc(U, As, trans='T', offsetx=k * (ns2))
            blas.tbmv(Gamma, As, n=ns2, k=0, ldA=1, offsetx=k * (ns2))

        misc.pack(As, Aspkd, {'l': 0, 'q': [], 's': [ns] * ms})

        # H is an m times m block matrix with i, k block
        #
        #      Hik = sum_j As[i,j]' * As[k,j]
        #
        # of size ms[i] x ms[k].  Hik = 0 if As[i,j] or As[k,j]
        # are zero for all j
        H = matrix(0.0, (ms, ms))
        blas.syrk(Aspkd, H, trans='T', beta=1.0, k=ns * (ns + 1) / 2)

        lapack.potrf(H)

        def solve(x, y, z):
            """
            Returns solution of 

                rho * ux + A'(uy) - r^-T * uz * r^-1 = bx
                A(ux)                                = by
                -ux               - r * uz * r'      = bz.

            On entry, x = bx, y = by, z = bz.
            On exit, x = ux, y = uy, z = uz.
            """

            # bz is a copy of z in the format of x
            blas.copy(z, bz)
            blas.axpy(bz, x, alpha=rho)

            # x := Gamma .* (u' * x * u)
            #    = Gamma .* (u' * (bx + rho * bz) * u)

            cngrnc(U, x, trans='T', offsetx=0)
            blas.tbmv(Gamma, x, n=ns2, k=0, ldA=1, offsetx=0)

            # y := y - As(x)
            #   := by - As( Gamma .* u' * (bx + rho * bz) * u)
            #blas.copy(x,xp)
            #pack_ip(xp,n = ns,m=1,nl=nl)
            misc.pack(x, xp, {'l': 0, 'q': [], 's': [ns]})

            blas.gemv(Aspkd, xp, y, trans = 'T',alpha = -1.0, beta = 1.0, \
                m = ns*(ns+1)/2, n = ms,offsetx = 0)

            # y := -y - A(bz)
            #    = -by - A(bz) + As(Gamma .*  (u' * (bx + rho * bz) * u)
            Af(bz, y, alpha=-1.0, beta=-1.0)

            # y := H^-1 * y
            #    = H^-1 ( -by - A(bz) + As(Gamma.* u'*(bx + rho*bz)*u) )
            #    = uy

            blas.trsv(H, y)
            blas.trsv(H, y, trans='T')

            # bz = Vt' * vz * Vt
            #    = uz where
            # vz := Gamma .* ( As'(uy)  - x )
            #     = Gamma .* ( As'(uy)  - Gamma .* (u'*(bx + rho *bz)*u) )
            #     = Gamma.^2 .* ( u' * (A'(uy) - bx - rho * bz) * u ).
            #blas.copy(x,xp)
            #pack_ip(xp,n=ns,m=1,nl=nl)

            misc.pack(x, xp, {'l': 0, 'q': [], 's': [ns]})
            blas.scal(-1.0, xp)

            blas.gemv(Aspkd,
                      y,
                      xp,
                      alpha=1.0,
                      beta=1.0,
                      m=ns * (ns + 1) / 2,
                      n=ms,
                      offsety=0)

            # bz[j] is xp unpacked and multiplied with Gamma
            misc.unpack(xp, bz, {'l': 0, 'q': [], 's': [ns]})
            blas.tbmv(Gamma, bz, n=ns2, k=0, ldA=1, offsetx=0)

            # bz = Vt' * bz * Vt
            #    = uz
            cngrnc(Vt, bz, trans='T', offsetx=0)

            symmetrize(bz, ns, offset=0)

            # x = -bz - r * uz * r'
            # z contains r.h.s. bz;  copy to x
            blas.copy(z, x)
            blas.copy(bz, z)

            cngrnc(W['r'][0], bz, offsetx=0)
            blas.axpy(bz, x)
            blas.scal(-1.0, x)

        return solve
def utility(x, y): 
    return (1.1 * sqrt(x) + 0.8 * sqrt(y)) / 1.9
예제 #33
0
    def F(W):
        """
        Generate a solver for

                                             A'(uz0) = bx[0]
                                          -uz0 - uz1 = bx[1] 
            A(ux[0]) - ux[1] - r0*r0' * uz0 * r0*r0' = bz0 
                     - ux[1] - r1*r1' * uz1 * r1*r1' = bz1.

        uz0, uz1, bz0, bz1 are symmetric m x m-matrices.
        ux[0], bx[0] are n-vectors.
        ux[1], bx[1] are symmetric m x m-matrices.

        We first calculate a congruence that diagonalizes r0*r0' and r1*r1':
 
            U' * r0 * r0' * U = I,  U' * r1 * r1' * U = S.

        We then make a change of variables

            usx[0] = ux[0],  
            usx[1] = U' * ux[1] * U  
              usz0 = U^-1 * uz0 * U^-T  
              usz1 = U^-1 * uz1 * U^-T 

        and define 

              As() = U' * A() * U'  
            bsx[1] = U^-1 * bx[1] * U^-T
              bsz0 = U' * bz0 * U  
              bsz1 = U' * bz1 * U.  

        This gives

                             As'(usz0) = bx[0]
                          -usz0 - usz1 = bsx[1] 
            As(usx[0]) - usx[1] - usz0 = bsz0 
                -usx[1] - S * usz1 * S = bsz1.


        1. Eliminate usz0, usz1 using equations 3 and 4,

               usz0 = As(usx[0]) - usx[1] - bsz0
               usz1 = -S^-1 * (usx[1] + bsz1) * S^-1.

           This gives two equations in usx[0] an usx[1].

               As'(As(usx[0]) - usx[1]) = bx[0] + As'(bsz0)

               -As(usx[0]) + usx[1] + S^-1 * usx[1] * S^-1
                   = bsx[1] - bsz0 - S^-1 * bsz1 * S^-1.


        2. Eliminate usx[1] using equation 2:

               usx[1] + S * usx[1] * S 
                   = S * ( As(usx[0]) + bsx[1] - bsz0 ) * S - bsz1

           i.e., with Gamma[i,j] = 1.0 + S[i,i] * S[j,j],
 
               usx[1] = ( S * As(usx[0]) * S ) ./ Gamma 
                        + ( S * ( bsx[1] - bsz0 ) * S - bsz1 ) ./ Gamma.

           This gives an equation in usx[0].

               As'( As(usx[0]) ./ Gamma ) 
                   = bx0 + As'(bsz0) + 
                     As'( (S * ( bsx[1] - bsz0 ) * S - bsz1) ./ Gamma )
                   = bx0 + As'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ Gamma ).

        """

        # Calculate U s.t. 
        # 
        #     U' * r0*r0' * U = I,   U' * r1*r1' * U = diag(s).
 
        # Cholesky factorization r0 * r0' = L * L'
        blas.syrk(W['r'][0], L)
        lapack.potrf(L)

        # SVD L^-1 * r1 = U * diag(s) * V'  
        blas.copy(W['r'][1], U)
        blas.trsm(L, U) 
        lapack.gesvd(U, s, jobu = 'O')

        # s := s**2
        s[:] = s**2

        # Uti := U
        blas.copy(U, Uti)

        # U := L^-T * U
        blas.trsm(L, U, transA = 'T')

        # Uti := L * Uti = U^-T 
        blas.trmm(L, Uti)

        # Us := U * diag(s)^-1
        blas.copy(U, Us)
        for i in range(m):
            blas.tbsv(s, Us, n = m, k = 0, ldA = 1, incx = m, offsetx = i)

        # S is m x m with lower triangular entries s[i] * s[j] 
        # sqrtG is m x m with lower triangular entries sqrt(1.0 + s[i]*s[j])
        # Upper triangular entries are undefined but nonzero.

        blas.scal(0.0, S)
        blas.syrk(s, S)
        Gamma = 1.0 + S
        sqrtG = sqrt(Gamma)


        # Asc[i] = (U' * Ai * * U ) ./  sqrtG,  for i = 1, ..., n
        #        = Asi ./ sqrt(Gamma)
        blas.copy(A, Asc)
        misc.scale(Asc,   # only 'r' part of the dictionary is used   
            {'dnl': matrix(0.0, (0, 1)), 'dnli': matrix(0.0, (0, 1)),
             'd': matrix(0.0, (0, 1)), 'di': matrix(0.0, (0, 1)),
             'v': [], 'beta': [], 'r': [ U ], 'rti': [ U ]}) 
        for i in range(n):
            blas.tbsv(sqrtG, Asc, n = msq, k = 0, ldA = 1, offsetx = i*msq)

        # Convert columns of Asc to packed storage
        misc.pack2(Asc, {'l': 0, 'q': [], 's': [ m ]})

        # Cholesky factorization of Asc' * Asc.
        H = matrix(0.0, (n, n))
        blas.syrk(Asc, H, trans = 'T', k = mpckd)
        lapack.potrf(H)


        def solve(x, y, z):
            """

            1. Solve for usx[0]:

               Asc'(Asc(usx[0]))
                   = bx0 + Asc'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ sqrtG)
                   = bx0 + Asc'( ( bsz0 + S * ( bsx[1] - bssz1) S ) 
                     ./ sqrtG)

               where bsx[1] = U^-1 * bx[1] * U^-T, bsz0 = U' * bz0 * U, 
               bsz1 = U' * bz1 * U, bssz1 = S^-1 * bsz1 * S^-1 

            2. Solve for usx[1]:

               usx[1] + S * usx[1] * S 
                   = S * ( As(usx[0]) + bsx[1] - bsz0 ) * S - bsz1 

               usx[1] 
                   = ( S * (As(usx[0]) + bsx[1] - bsz0) * S - bsz1) ./ Gamma
                   = -bsz0 + (S * As(usx[0]) * S) ./ Gamma
                     + (bsz0 - bsz1 + S * bsx[1] * S ) . / Gamma
                   = -bsz0 + (S * As(usx[0]) * S) ./ Gamma
                     + (bsz0 + S * ( bsx[1] - bssz1 ) * S ) . / Gamma

               Unscale ux[1] = Uti * usx[1] * Uti'

            3. Compute usz0, usz1

               r0' * uz0 * r0 = r0^-1 * ( A(ux[0]) - ux[1] - bz0 ) * r0^-T
               r1' * uz1 * r1 = r1^-1 * ( -ux[1] - bz1 ) * r1^-T

            """

            # z0 := U' * z0 * U 
            #     = bsz0
            __cngrnc(U, z, trans = 'T')

            # z1 := Us' * bz1 * Us 
            #     = S^-1 * U' * bz1 * U * S^-1
            #     = S^-1 * bsz1 * S^-1
            __cngrnc(Us, z, trans = 'T', offsetx = msq)

            # x[1] := Uti' * x[1] * Uti 
            #       = bsx[1]
            __cngrnc(Uti, x[1], trans = 'T')
        
            # x[1] := x[1] - z[msq:] 
            #       = bsx[1] - S^-1 * bsz1 * S^-1
            blas.axpy(z, x[1], alpha = -1.0, offsetx = msq)


            # x1 = (S * x[1] * S + z[:msq] ) ./ sqrtG
            #    = (S * ( bsx[1] - S^-1 * bsz1 * S^-1) * S + bsz0 ) ./ sqrtG
            #    = (S * bsx[1] * S - bsz1 + bsz0 ) ./ sqrtG
            # in packed storage
            blas.copy(x[1], x1)
            blas.tbmv(S, x1, n = msq, k = 0, ldA = 1)
            blas.axpy(z, x1, n = msq)
            blas.tbsv(sqrtG, x1, n = msq, k = 0, ldA = 1)
            misc.pack2(x1, {'l': 0, 'q': [], 's': [m]})

            # x[0] := x[0] + Asc'*x1 
            #       = bx0 + Asc'( ( bsz0 - bsz1 + S * bsx[1] * S ) ./ sqrtG)
            #       = bx0 + As'( ( bz0 - bz1 + S * bx[1] * S ) ./ Gamma )
            blas.gemv(Asc, x1, x[0], m = mpckd, trans = 'T', beta = 1.0)

            # x[0] := H^-1 * x[0]
            #       = ux[0]
            lapack.potrs(H, x[0])


            # x1 = Asc(x[0]) .* sqrtG  (unpacked)
            #    = As(x[0])  
            blas.gemv(Asc, x[0], tmp, m = mpckd)
            misc.unpack(tmp, x1, {'l': 0, 'q': [], 's': [m]})
            blas.tbmv(sqrtG, x1, n = msq, k = 0, ldA = 1)


            # usx[1] = (x1 + (x[1] - z[:msq])) ./ sqrtG**2 
            #        = (As(ux[0]) + bsx[1] - bsz0 - S^-1 * bsz1 * S^-1) 
            #           ./ Gamma

            # x[1] := x[1] - z[:msq] 
            #       = bsx[1] - bsz0 - S^-1 * bsz1 * S^-1
            blas.axpy(z, x[1], -1.0, n = msq)

            # x[1] := x[1] + x1
            #       = As(ux) + bsx[1] - bsz0 - S^-1 * bsz1 * S^-1 
            blas.axpy(x1, x[1])

            # x[1] := x[1] / Gammma
            #       = (As(ux) + bsx[1] - bsz0 + S^-1 * bsz1 * S^-1 ) / Gamma
            #       = S^-1 * usx[1] * S^-1
            blas.tbsv(Gamma, x[1], n = msq, k = 0, ldA = 1)
            

            # z[msq:] := r1' * U * (-z[msq:] - x[1]) * U * r1
            #         := -r1' * U * S^-1 * (bsz1 + ux[1]) * S^-1 *  U * r1
            #         := -r1' * uz1 * r1
            blas.axpy(x[1], z, n = msq, offsety = msq)
            blas.scal(-1.0, z, offset = msq)
            __cngrnc(U, z, offsetx = msq)
            __cngrnc(W['r'][1], z, trans = 'T', offsetx = msq)

            # x[1] :=  S * x[1] * S
            #       =  usx1 
            blas.tbmv(S, x[1], n = msq, k = 0, ldA = 1)

            # z[:msq] = r0' * U' * ( x1 - x[1] - z[:msq] ) * U * r0
            #         = r0' * U' * ( As(ux) - usx1 - bsz0 ) * U * r0
            #         = r0' * U' *  usz0 * U * r0
            #         = r0' * uz0 * r0
            blas.axpy(x1, z, -1.0, n = msq)
            blas.scal(-1.0, z, n = msq)
            blas.axpy(x[1], z, -1.0, n = msq)
            __cngrnc(U, z)
            __cngrnc(W['r'][0], z, trans = 'T')

            # x[1] := Uti * x[1] * Uti'
            #       = ux[1]
            __cngrnc(Uti, x[1])


        return solve
예제 #34
0
파일: robls.py 프로젝트: sfu-db/quicksel
# least squares solution:  minimize || A*x - b ||_2^2
xls = +b
lapack.gels(+A, xls)
xls = xls[:n]

# Tikhonov solution:  minimize || A*x - b ||_2^2 + 0.1*||x||^2_2
xtik = A.T * b
S = A.T * A
S[::n + 1] += 0.1
lapack.posv(S, xtik)

# Worst case solution
xwc = wcls(A, Ap, b)

notrials = 100000
r = sqrt(uniform(1, notrials))
theta = 2.0 * pi * uniform(1, notrials)
u = matrix(0.0, (2, notrials))
u[0, :] = mul(r, cos(theta))
u[1, :] = mul(r, sin(theta))

# LS solution
q = A * xls - b
P = matrix(0.0, (m, 2))
P[:, 0], P[:, 1] = Ap[0] * xls, Ap[1] * xls
r = P * u + q[:, notrials * [0]]
resls = sqrt(matrix(1.0, (1, m)) * mul(r, r))

q = A * xtik - b
P[:, 0], P[:, 1] = Ap[0] * xtik, Ap[1] * xtik
r = P * u + q[:, notrials * [0]]
예제 #35
0
        def kkt(W):
            """
            KKT solver for

                X*X' * ux  + uy * 1_m' + mat(uz) = bx
                                       ux * 1_m  = by
                            ux - d.^2 .* mat(uz) = mat(bz).

            ux and bx are N x m matrices.
            uy and by are N-vectors.
            uz and bz are N*m-vectors.  mat(uz) is the N x m matrix that 
                satisfies mat(uz)[:] = uz.
            d = mat(W['d']) a positive N x m matrix.

            If we eliminate uz from the last equation using 

                mat(uz) = (ux - mat(bz)) ./ d.^2
        
            we get two equations in ux, uy:

                X*X' * ux + ux ./ d.^2 + uy * 1_m' = bx + mat(bz) ./ d.^2
                                          ux * 1_m = by.

            From the 1st equation,

                uxk = (X*X' + Dk^-2)^-1 * (-uy + bxk + Dk^-2 * bzk)
                    = Dk * (I + Xk*Xk')^-1 * Dk * (-uy + bxk + Dk^-2 * bzk)

            for k = 1, ..., m, where Dk = diag(d[:,k]), Xk = Dk * X, 
            uxk is column k of ux, and bzk is column k of mat(bz).  

            We use the matrix inversion lemma

                ( I + Xk * Xk' )^-1 = I - Xk * (I + Xk' * Xk)^-1 * Xk'
                                    = I - Xk * Hk^-1 * Xk'
                                    = I - Xk * Lk^-T * Lk^-1 *  Xk'

            where Hk = I + Xk' * Xk = Lk * Lk' to write this as

                uxk = Dk * (I - Xk * Hk^-1 * Xk') * Dk *
                      (-uy + bxk + Dk^-2 * bzk)
                    = (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2) *
                      (-uy + bxk + Dk^-2 * bzk).

            Substituting this in the second equation gives an equation 
            for uy:

                sum_k (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2 ) * uy 
                    = -by + sum_k (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2) *
                      ( bxk + Dk^-2 * bzk ),

            i.e., with D = (sum_k Dk^2)^1/2,  Yk = D^-1 * Dk^2 * X * Lk^-T,

                D * ( I - sum_k Yk * Yk' ) * D * uy  
                    = -by + sum_k (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2) * 
                      ( bxk + Dk^-2 *bzk ).

            Another application of the matrix inversion lemma gives

                uy = D^-1 * (I + Y * S^-1 * Y') * D^-1 * 
                     ( -by + sum_k ( Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2 ) *
                     ( bxk + Dk^-2 *bzk ) )

            with S = I - Y' * Y,  Y = [ Y1 ... Ym ].  


            Summary:

            1. Compute 

                   uy = D^-1 * (I + Y * S^-1 * Y') * D^-1 * 
                        ( -by + sum_k (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2)
                        * ( bxk + Dk^-2 *bzk ) )
 
            2. For k = 1, ..., m:

                   uxk = (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2) * 
                         (-uy + bxk + Dk^-2 * bzk)

            3. Solve for uz

                   d .* uz = ( ux - mat(bz) ) ./ d.
        
            Return ux, uy, d .* uz.

            """
            ###
            utime0, stime0 = cputime()
            ###

            d = matrix(W['d'], (N, m))
            dsq = matrix(W['d']**2, (N, m))

            # Factor the matrices
            #
            #     H[k] = I + Xk' * Xk
            #          = I + X' * Dk^2 * X.
            #
            # Dk = diag(d[:,k]).

            for k in range(m):

                # H[k] = I
                blas.scal(0.0, H[k])
                H[k][::n + 1] = 1.0

                # Xs = Dk * X
                #    = diag(d[:,k]]) * X
                blas.copy(X, Xs)
                for j in range(n):
                    blas.tbmv(d,
                              Xs,
                              n=N,
                              k=0,
                              ldA=1,
                              offsetA=k * N,
                              offsetx=j * N)

                # H[k] := H[k] + Xs' * Xs
                #       = I + Xk' * Xk
                blas.syrk(Xs, H[k], trans='T', beta=1.0)

                # Factorization H[k] = Lk * Lk'
                lapack.potrf(H[k])

###
            utime, stime = cputime()
            print("Factor Hk's: utime = %.2f, stime = %.2f" \
                %(utime-utime0, stime-stime0))
            utime0, stime0 = cputime()
            ###

            # diag(D) = ( sum_k d[:,k]**2 ) ** 1/2
            #         = ( sum_k Dk^2) ** 1/2.

            blas.gemv(dsq, ones, D)
            D[:] = sqrt(D)

            ###
            #            utime, stime = cputime()
            #            print("Compute D:  utime = %.2f, stime = %.2f" \
            #                %(utime-utime0, stime-stime0))
            utime0, stime0 = cputime()
            ###

            # S = I - Y'* Y is an m x m block matrix.
            # The i,j block of Y' * Y is
            #
            #     Yi' * Yj = Li^-1 * X' * Di^2 * D^-1 * Dj^2 * X * Lj^-T.
            #
            # We compute only the lower triangular blocks in Y'*Y.

            blas.scal(0.0, S)
            for i in range(m):
                for j in range(i + 1):

                    # Xs = Di * Dj * D^-1 * X
                    blas.copy(X, Xs)
                    blas.copy(d, wN, n=N, offsetx=i * N)
                    blas.tbmv(d, wN, n=N, k=0, ldA=1, offsetA=j * N)
                    blas.tbsv(D, wN, n=N, k=0, ldA=1)
                    for k in range(n):
                        blas.tbmv(wN, Xs, n=N, k=0, ldA=1, offsetx=k * N)

                    # block i, j of S is Xs' * Xs (as nonsymmetric matrix so we
                    # get the correct multiple after scaling with Li, Lj)
                    blas.gemm(Xs,
                              Xs,
                              S,
                              transA='T',
                              ldC=m * n,
                              offsetC=(j * n) * m * n + i * n)

###
            utime, stime = cputime()
            print("Form S:      utime = %.2f, stime = %.2f" \
                %(utime-utime0, stime-stime0))
            utime0, stime0 = cputime()
            ###

            for i in range(m):

                # multiply block row i of S on the left with Li^-1
                blas.trsm(H[i],
                          S,
                          m=n,
                          n=(i + 1) * n,
                          ldB=m * n,
                          offsetB=i * n)

                # multiply block column i of S on the right with Li^-T
                blas.trsm(H[i],
                          S,
                          side='R',
                          transA='T',
                          m=(m - i) * n,
                          n=n,
                          ldB=m * n,
                          offsetB=i * n * (m * n + 1))

            blas.scal(-1.0, S)
            S[::(m * n + 1)] += 1.0

            ###
            utime, stime = cputime()
            print("Form S (2):  utime = %.2f, stime = %.2f" \
                %(utime-utime0, stime-stime0))
            utime0, stime0 = cputime()
            ###

            # S = L*L'
            lapack.potrf(S)

            ###
            utime, stime = cputime()
            print("Factor S:    utime = %.2f, stime = %.2f" \
                %(utime-utime0, stime-stime0))
            utime0, stime0 = cputime()

            ###

            def f(x, y, z):
                """
                1. Compute 

                   uy = D^-1 * (I + Y * S^-1 * Y') * D^-1 * 
                        ( -by + sum_k (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2)
                        * ( bxk + Dk^-2 *bzk ) )
 
                2. For k = 1, ..., m:

                   uxk = (Dk^2 - Dk^2 * X * Hk^-1 * X' * Dk^2) * 
                         (-uy + bxk + Dk^-2 * bzk)

                3. Solve for uz

                   d .* uz = ( ux - mat(bz) ) ./ d.
        
                Return ux, uy, d .* uz.
                """

                ###
                utime0, stime0 = cputime()
                ###

                # xk := Dk^2 * xk + zk
                #     = Dk^2 * bxk + bzk
                blas.tbmv(dsq, x, n=N * m, k=0, ldA=1)
                blas.axpy(z, x)

                # y := -y + sum_k ( I - Dk^2 * X * Hk^-1 * X' ) * xk
                #    = -y + x*ones - sum_k Dk^2 * X * Hk^-1 * X' * xk

                # y := -y + x*ones
                blas.gemv(x, ones, y, alpha=1.0, beta=-1.0)

                # wnm = X' * x  (wnm interpreted as an n x m matrix)
                blas.gemm(X, x, wnm, m=n, k=N, n=m, transA='T', ldB=N, ldC=n)

                # wnm[:,k] = Hk \ wnm[:,k] (for wnm as an n x m matrix)
                for k in range(m):
                    lapack.potrs(H[k], wnm, offsetB=k * n)

                for k in range(m):

                    # wN = X * wnm[:,k]
                    blas.gemv(X, wnm, wN, offsetx=n * k)

                    # wN = Dk^2 * wN
                    blas.tbmv(dsq[:, k], wN, n=N, k=0, ldA=1)

                    # y := y - wN
                    blas.axpy(wN, y, -1.0)

                # y = D^-1 * (I + Y * S^-1 * Y') * D^-1 * y
                #
                # Y = [Y1 ... Ym ], Yk = D^-1 * Dk^2 * X * Lk^-T.

                # y := D^-1 * y
                blas.tbsv(D, y, n=N, k=0, ldA=1)

                # wnm =  Y' * y  (interpreted as an Nm vector)
                #     = [ L1^-1 * X' * D1^2 * D^-1 * y;
                #         L2^-1 * X' * D2^2 * D^-1 * y;
                #         ...
                #         Lm^-1 * X' * Dm^2 * D^-1 * y ]

                for k in range(m):

                    # wN = D^-1 * Dk^2 * y
                    blas.copy(y, wN)
                    blas.tbmv(dsq, wN, n=N, k=0, ldA=1, offsetA=k * N)
                    blas.tbsv(D, wN, n=N, k=0, ldA=1)

                    # wnm[:,k] = X' * wN
                    blas.gemv(X, wN, wnm, trans='T', offsety=k * n)

                    # wnm[:,k] = Lk^-1 * wnm[:,k]
                    blas.trsv(H[k], wnm, offsetx=k * n)

                # wnm := S^-1 * wnm  (an mn-vector)
                lapack.potrs(S, wnm)

                # y := y + Y * wnm
                #    = y + D^-1 * [ D1^2 * X * L1^-T ... D2^k * X * Lk^-T]
                #      * wnm

                for k in range(m):

                    # wnm[:,k] = Lk^-T * wnm[:,k]
                    blas.trsv(H[k], wnm, trans='T', offsetx=k * n)

                    # wN = X * wnm[:,k]
                    blas.gemv(X, wnm, wN, offsetx=k * n)

                    # wN = D^-1 * Dk^2 * wN
                    blas.tbmv(dsq, wN, n=N, k=0, ldA=1, offsetA=k * N)
                    blas.tbsv(D, wN, n=N, k=0, ldA=1)

                    # y += wN
                    blas.axpy(wN, y)

                # y := D^-1 *  y
                blas.tbsv(D, y, n=N, k=0, ldA=1)

                # For k = 1, ..., m:
                #
                # xk = (I - Dk^2 * X * Hk^-1 * X') * (-Dk^2 * y + xk)

                # x = x - [ D1^2 * y ... Dm^2 * y] (as an N x m matrix)
                for k in range(m):
                    blas.copy(y, wN)
                    blas.tbmv(dsq, wN, n=N, k=0, ldA=1, offsetA=k * N)
                    blas.axpy(wN, x, -1.0, offsety=k * N)

                # wnm  = X' * x (as an n x m matrix)
                blas.gemm(X, x, wnm, transA='T', m=n, n=m, k=N, ldB=N, ldC=n)

                # wnm[:,k] = Hk^-1 * wnm[:,k]
                for k in range(m):
                    lapack.potrs(H[k], wnm, offsetB=n * k)

                for k in range(m):

                    # wN = X * wnm[:,k]
                    blas.gemv(X, wnm, wN, offsetx=k * n)

                    # wN = Dk^2 * wN
                    blas.tbmv(dsq, wN, n=N, k=0, ldA=1, offsetA=k * N)

                    # x[:,k] := x[:,k] - wN
                    blas.axpy(wN, x, -1.0, n=N, offsety=k * N)

                # z := ( x - z ) ./ d
                blas.axpy(x, z, -1.0)
                blas.scal(-1.0, z)
                blas.tbsv(d, z, n=N * m, k=0, ldA=1)

                ###
                utime, stime = cputime()
                print("Solve:       utime = %.2f, stime = %.2f" \
                    %(utime-utime0, stime-stime0))


###

            return f
예제 #36
0
    def _build_conelp(self):
        Nx = self.nbus
        self.Nx = Nx
        nflow_constr = len(self.branches_with_flow_constraints())
        npad_constr = len(self.branches_with_pad_constraints())
        ngen_var_p = len(self.generators_with_var_real_power())
        ngen_qcost = len(self.generators_with_var_real_power_and_quadratic_cost())
        ngen_lcost = len(self.generators_with_var_real_power_and_linear_cost())
        self._ngen_var_p = ngen_var_p
        ngen_var_q = len(self.generators_with_var_reactive_power())
        self._ngen_var_q = ngen_var_q

        dims = {}
        dims['l'] = 2*self.nbus + 2*ngen_var_p + 2*ngen_var_q + ngen_qcost + 2*npad_constr
        dims['q'] = 2*nflow_constr*[3]
        dims['q'] += ngen_qcost*[3]
        dims['s'] = [Nx]

        offset = {}
        offset['t'] = 0                             # t   = aux. vars for epigraph formulation of quad. gen. power cost
        offset['wpl'] = offset['t'] + ngen_qcost    # wpl = slack lower bnd: Pmin[i] + wpl[i] = Pg[i]
        offset['wpu'] = offset['wpl'] + ngen_var_p  # wpu = slack upper bnd: Pg[i] + wpu[i] = Pmax[i]
        offset['wql'] = offset['wpu'] + ngen_var_p  # wql = slack lower bnd: Qmin[i] + wql[i] = Qg[i]
        offset['wqu'] = offset['wql'] + ngen_var_q  # wqu = slack upper bnd: Qg[i] + wqu[i] = Qmax[i]
        offset['ul'] = offset['wqu'] + ngen_var_q   # ul  = slack lower bnd: Vmin[i]**2 + ul[i] = abs(V[i])
        offset['uu'] = offset['ul'] + self.nbus     # uu  = slack upper bnd: abs(V[i]) + uu[i] = Vmax[i]**2
        offset['lpad'] = offset['uu'] + self.nbus
        offset['upad'] = offset['lpad'] + npad_constr
        offset['z'] = offset['upad'] + npad_constr  # z   = line flow const: z[k*3:(k+1)*3] in SOC of dim 3
        offset['w'] =  offset['z'] + sum(dims['q'])-3*ngen_qcost  # w  = epigraph of quad. gen cost: w[k*3:(k+1)*3] in SOC of dim 3
        offset['X'] = offset['w'] + 3*ngen_qcost                  # X  = SDR of X = V*V.H
        N = offset['X'] + Nx**2
        self.offset = offset

        dual_offset = [0]
        # power balance
        dual_offset.append(dual_offset[-1] + 2*self.ngen)
        # gen. limits (real)
        dual_offset.append(dual_offset[-1] + len(self.generators_with_var_real_power()))
        # gen. limits (reactive)
        dual_offset.append(dual_offset[-1] + len(self.generators_with_var_reactive_power()))
        # voltage constraints
        dual_offset.append(dual_offset[-1] + 2*self.nbus)
        # line constraints
        dual_offset.append(dual_offset[-1] + 6*len(self.branches_with_flow_constraints()))
        # pad pad_constraints
        dual_offset.append(dual_offset[-1] + 2*npad_constr)
        # quad. cost
        dual_offset.append(dual_offset[-1] + 3*len(self.generators_with_var_real_power_and_quadratic_cost()))

        self.dual_offset = matrix(dual_offset)

        ##
        ## Build h and initialize c
        ##
        I,V = [],[]
        for k,gen in enumerate(self. generators_with_var_real_power()):
            beta = gen['Pcost']['coef'][-2]
            if gen['Pcost']['ncoef'] > 2: beta += 2.0*self.baseMVA*gen['Pcost']['coef'][-3]*gen['Pmin']
            I.append(offset['wpl'] + gen['pslack'])
            V.append(beta)
        h = spmatrix(ngen_qcost*[1.0]+V, list(range(ngen_qcost))+I, (ngen_qcost+len(I))*[0], (N,1))
        c = []

        ##
        ## Initialize lists for triplet storage of columns in G
        ##
        I,V = [],[]

        ##
        ## Power balance constraints
        ##
        rp,ci,val = self.Ybus.T.CCS
        def conj(l): return [li.conjugate() for li in l]
        def smul(l): return [-li for li in l]
        def jmul(l):
           j = complex(0.0,1.0)
           return [j*li for li in l]

        def Yijv(k):
            jj = list(ci[rp[k]:rp[k+1]])
            ii = len(jj)*[k]
            vv = list(0.5*val[rp[k]:rp[k+1]])
            t = jj.index(k)
            Iret = t*[k]+jj+(len(jj)-1-t)*[k]
            Jret = jj[:t]+len(jj)*[k]+jj[t+1:]
            Vret = vv[:t] + conj(vv[:t]) + [2.0*vv[t].real] + conj(vv[t+1:]) + vv[t+1:]
            Vbret = vv[:t] + smul(conj(vv[:t])) + [complex(0.0,2.0*vv[t].imag)] + smul(conj(vv[t+1:])) + vv[t+1:]
            return Iret,Jret,Vret,jmul(Vbret)

        for k, bus in enumerate(self.busses):

            YI,YJ,YV,YbV = Yijv(k)

            if bus['id'] in self.bus_id_to_genlist:
                genlist = [self.generators[i] for i in self.bus_id_to_genlist[bus['id']]]

                L = [offset['X'] + ii + jj*Nx for ii,jj in zip(YI,YJ)]
                I.append([offset['wpl']+gen['pslack'] for gen in genlist if gen['pslack'] is not None] + L)
                V.append(len([1 for gen in genlist if gen['pslack'] is not None])*[-1.0] + YV)
                c.append(bus['Pd'] - sum([gen['Pmin'] for gen in genlist]))

                L = [offset['X'] + ii + jj*Nx for ii,jj in zip(YI,YJ)]
                I.append([offset['wql']+gen['qslack'] for gen in genlist if gen['qslack'] is not None] + L)
                V.append(len([1 for gen in genlist if gen['qslack'] is not None])*[-1.0] + YbV)
                c.append(bus['Qd'] - sum([gen['Qmin'] for gen in genlist]))

            else:
                L = [offset['X'] + ii + jj*Nx for ii,jj in zip(YI,YJ)]
                I.append(L)
                V.append(YV)
                c.append(bus['Pd'])

                L = [offset['X'] + ii + jj*Nx for ii,jj in zip(YI,YJ)]
                I.append(L)
                V.append(YbV)
                c.append(bus['Qd'])

        ##
        ## Power generation limits
        ##
        for k, gen in enumerate(self.generators_with_var_real_power()):
            I.append([offset['wpl']+k, offset['wpu']+k])
            V.append([1.0, 1.0])
            c.append(gen['Pmin'] - gen['Pmax'])

        for k, gen in enumerate(self.generators_with_var_reactive_power()):
            I.append([offset['wql']+k, offset['wqu']+k])
            V.append([1.0, 1.0])
            c.append(gen['Qmin'] - gen['Qmax'])

        ##
        ## Voltage constraints
        ##
        for k, bus in enumerate(self.busses):
            I.append([offset['ul']+k, offset['X']+k*(self.nbus+1)])
            V.append([1.0, -1.0])
            c.append(bus['minVm']**2)
        for k, bus in enumerate(self.busses):
            I.append([offset['uu']+k, offset['X']+k*(self.nbus+1)])
            V.append([1.0, 1.0])
            c.append(-bus['maxVm']**2)

        ##
        ## Line constraints
        ##
        rpf,cif,valf = self.Yf.T.CCS
        rpt,cit,valt = self.Yt.T.CCS
        def Tijv(k, fr, to, flow = 'ft'):
            if flow == 'ft':
                y = self.Ybr[k][0]
                if fr > to:
                   y.reverse()
                   fr,to = to,fr
                   flow = 'tf'
            elif flow == 'tf':
                y = self.Ybr[k][1]
                if fr > to:
                   y.reverse()
                   fr,to = to,fr
                   flow = 'ft'
            if flow == 'ft':
               Iret = [fr,to,fr]
               Jret = [fr,fr,to]
               Tret = [y[0].real, 0.5*y[1].conjugate(), 0.5*y[1]]
               Tbret = [-y[0].imag, -complex(0.0,0.5)*y[1].conjugate(), complex(0.0,0.5)*y[1]]
            elif flow == 'tf':
               Iret = [to,fr,to]
               Jret = [fr,to,to]
               Tret = [0.5*y[0],0.5*y[0].conjugate(),y[1].real]
               Tbret = [complex(0.0,0.5)*y[0],-complex(0.0,0.5)*y[0].conjugate(),-y[1].imag]
            return Iret,Jret,Tret,Tbret

        for kk,kbranch in enumerate(self.branches_with_flow_constraints()):
            k,branch = kbranch

            fr = self.bus_id_to_index[branch['from']]
            to = self.bus_id_to_index[branch['to']]

            # flow at "from" end
            Ir,Jr,Vr,Vbr = Tijv(k,fr,to,'ft')

            I.append([offset['z']+6*kk])
            V.append([1.0])
            c.append(-branch['rateA']/self.baseMVA)

            I.append([offset['z']+6*kk+1] + [offset['X'] + ii + jj*Nx for ii,jj in zip(Ir,Jr)])
            V.append([-1.0] + Vr)
            c.append(0.0)

            I.append([offset['z']+6*kk+2] + [offset['X'] + ii + jj*Nx for ii,jj in zip(Ir,Jr)])
            V.append([-1.0] + Vbr)
            c.append(0.0)

            # flow at "to" end
            Ir,Jr,Vr,Vbr = Tijv(k,fr,to,'tf')

            I.append([offset['z']+6*kk+3])
            V.append([1.0])
            c.append(-branch['rateA']/self.baseMVA)

            I.append([offset['z']+6*kk+4] + [offset['X'] + ii + jj*Nx for ii,jj in zip(Ir,Jr)])
            V.append([-1.0] + Vr)
            c.append(0.0)

            I.append([offset['z']+6*kk+5] + [offset['X'] + ii + jj*Nx for ii,jj in zip(Ir,Jr)])
            V.append([-1.0] + Vbr)
            c.append(0.0)

        ##
        ## Phase angle difference constraints
        ##
        for kk,kbranch in enumerate(self.branches_with_pad_constraints()):
            k,branch = kbranch
            tan_amin = tan(branch['angle_min']*pi/180.0)
            f = self.bus_id_to_index[branch['from']]
            t = self.bus_id_to_index[branch['to']]
            I.append([offset['lpad']+kk] + [offset['X']+f+t*Nx,offset['X']+t+f*Nx])
            V.append([1.0] + [complex(0.5*tan_amin,0.5), complex(0.5*tan_amin,-0.5)])
            c.append(0.0)
        for kk,kbranch in enumerate(self.branches_with_pad_constraints()):
            k,branch = kbranch
            tan_amax = tan(branch['angle_max']*pi/180.0)
            f = self.bus_id_to_index[branch['from']]
            t = self.bus_id_to_index[branch['to']]
            I.append([offset['upad']+kk] + [offset['X']+f+t*Nx,offset['X']+t+f*Nx])
            V.append([1.0] + [-complex(0.5*tan_amax,0.5), -complex(0.5*tan_amax,-0.5)])
            c.append(0.0)

        ##
        ## Quadratic cost -- epigraph
        ##
        for k, gen in enumerate(self.generators_with_var_real_power_and_quadratic_cost()):

            assert gen['Pcost']['ncoef'] == 3, "only quadratic cost implemented"
            assert gen['Pcost']['model'] == 2, "only quadratic cost implemented"
            ak = gen['Pcost']['coef'][-3]*self.baseMVA

            I.append([offset['t']+k,  offset['w']+3*k])
            V.append([1.0, -1.0])
            c.append(0.5)

            I.append([offset['t']+k,  offset['w']+3*k+1])
            V.append([-1.0, -1.0])
            c.append(0.5)

            I.append([offset['wpl']+gen['pslack'], offset['w']+3*k+2])
            V.append([sqrt(2.0*ak), -1.0])
            c.append(0.0)

        ##
        ## Fixed cost
        ##
        self.const_cost = 0.0
        for kk,gen in enumerate(self.generators):
            if gen['Pcost']['ncoef'] == 2 or (gen['Pcost']['ncoef'] == 3 and gen['Pcost']['coef'][0] == 0.0):
                self.const_cost += gen['Pcost']['coef'][-1]/self.baseMVA + gen['Pcost']['coef'][-2]*gen['Pmin']
            elif gen['Pcost']['ncoef'] == 3:
                self.const_cost += gen['Pcost']['coef'][-1]/self.baseMVA \
                  + gen['Pcost']['coef'][-2]*gen['Pmin'] \
                  + self.baseMVA*gen['Pcost']['coef'][-3]*gen['Pmin']**2
        self.const_cost *= self.baseMVA

        ##
        ## Build c, h, and G
        ##
        c = matrix(c)
        J = [len(Ii)*[j] for j,Ii in enumerate(I)]
        G = spmatrix([v for v in chain(*V)],
                     [v for v in chain(*I)],
                     [v for v in chain(*J)],(N,len(c)))

        self.problem_data = (c, G, h, dims)
        return
예제 #37
0
def solve(A, b, C, L, dims, proxqp=None, sigma=1.0, rho=1.0, **kwargs):
    """
    
    Solves the SDP

        min.  < c, x > 
        s.t.  A(x) = b
              x >= 0

    and its dual

        max.  -< b, y > 
        s.t.  s >= 0.
             c + A'(y) = s 
    
    
    Input arguments.
    
        A   is an N x M sparse matrix where N = sum_i ns[i]**2 and M = sum_j ms[j]
            and ns and ms are the SDP variable sizes and constraint block lengths respectively.
            
            The expression A(x) = b can be written as A.T*xtilde = b, where
            xtilde is a stacked vector of vectorized versions of xi.
        
        b   is a stacked vector containing constraint vectors of 
                        size m_i x 1.
    
        C   is a stacked vector containing vectorized 'd' matrices 
            c_k of size n_k**2 x 1, representing symmetric matrices.



        L  is an N X P sparse matrix, where L.T*X = 0 represents the consistency
            constraints. If an index k appears in different cliques i,j, and
            in converted form are indexed by it, jt, then L[it,l] = 1, 
            L[jt,l] = -1 for some l.
            
        dims    is a dictionary containing conic dimensions.
            dims['l'] contains number of linear variables under nonnegativity constrant
            dims['q'] contains a list of quadratic cone orders (not implemented!)
            dims['s'] contains a list of semidefinite cone matrix orders
        
        proxqp   is either a function pointer to a prox implementation, or, if 
                the problem has block-diagonal correlative sparsity, a pointer 
                to the prox implementation of a single clique. The choices are:
                
                proxqp_general : solves prox for general sparsity pattern
                
                proxqp_clique : solves prox for a single dense clique with 
                                only semidefinite variables.
                
                proxqp_clique_SNL : solves prox for sensor network localization 
                                    problem
        
        sigma is a nonnegative constant (step size)
        
        rho is a nonnegative constaint between 0 and 2 (overrelaxation parameter)
        
        In addition, the following paramters are optional:
        
            maxiter : maximum number of iterations (default 100)
            
            reltol : relative tolerance (default 0.01). 
                        If rp < reltol and rd < reltol and iteration < maxiter, 
                        solver breaks and returns current value.
                        
            adaptive : boolean toggle on whether adaptive step size should be 
                        used. (default False)
            
            mu, tau, tauscale : parameters for adaptive step size (see paper)

            multiprocess : number of parallel processes (default 1). 
                            if multiprocess = 1, no parallelization is used.
                            
            blockdiagonal : boolean toggle on whether problem has block diagonal
                            correlative sparsity. Note that even if the problem
                            does have block-diagonal correlative sparsity, if
                            this parameter is set to False, then general mode 
                            is used. (default False)
                            

            verbose : toggle printout (default True)
            
            log_cputime : toggle whether cputime should be logged.
	    
	    
    The output is returned in a dictionary with the following files:
        
        x : primal variable in stacked form (X = [x0, ..., x_{N-1}]) where
            xk is the vectorized form of the nk x nk submatrix variable.
        
        y, z : iterates in Spingarn's method
        
        cputime, walltime : total cputime and walltime, respectively, spent in 
                            main loop. If log_cputime is False, then cputime is 
                            returned as 0.
        
        primal, rprimal, rdual : evolution of primal optimal value, primal 
                                residual, and dual residual (resp.)
        
        sigma : evolution of step size sigma (changes if adaptive step size is used.)
    

    """

    solvers.options['show_progress'] = False
    maxiter = kwargs.get('maxiter', 100)
    reltol = kwargs.get('reltol', 0.01)
    adaptive = kwargs.get('adaptive', False)
    mu = kwargs.get('mu', 2.0)
    tau = kwargs.get('tau', 1.5)
    multiprocess = kwargs.get('multiprocess', 1)
    tauscale = kwargs.get('tauscale', 0.9)
    blockdiagonal = kwargs.get('blockdiagonal', False)
    verbose = kwargs.get('verbose', True)
    log_cputime = kwargs.get('log_cputime', True)

    if log_cputime:
        try:
            import psutil
        except (ImportError):
            assert False, "Python package psutil required to log cputime. Package can be downloaded at http://code.google.com/p/psutil/"

    #format variables
    nl, ns = dims['l'], dims['s']
    C = C[nl:]
    L = L[nl:, :]
    As, bs = [], []
    cons = []
    offset = 0
    for k in xrange(len(ns)):
        Atmp = sparse(A[nl + offset:nl + offset + ns[k]**2, :])
        J = list(set(list(Atmp.J)))
        Atmp = Atmp[:, J]
        if len(sparse(Atmp).V) == Atmp[:].size[0]: Atmp = matrix(Atmp)
        else: Atmp = sparse(Atmp)
        As.append(Atmp)
        bs.append(b[J])
        cons.append(J)

        offset += ns[k]**2

    if blockdiagonal:
        if sum([len(c) for c in cons]) > len(b):
            print "Problem does not have block-diagonal correlative sparsity. Switching to general mode."
            blockdiagonal = False

    #If not block-diagonal correlative sprasity, represent A as a list of lists:
    #   A[i][j] is a matrix (or spmatrix) if ith clique involves jth constraint block
    #Otherwise, A is a list of matrices, where A[i] involves the ith clique and
    #ith constraint block only.

    if not blockdiagonal:
        while sum([len(c) for c in cons]) > len(b):
            tobreak = False
            for i in xrange(len(cons)):
                for j in xrange(i):
                    ci, cj = set(cons[i]), set(cons[j])
                    s1 = ci.intersection(cj)
                    if len(s1) > 0:
                        s2 = ci.difference(cj)
                        s3 = cj.difference(ci)
                        cons.append(list(s1))
                        if len(s2) > 0:
                            s2 = list(s2)
                            if not (s2 in cons): cons.append(s2)
                        if len(s3) > 0:
                            s3 = list(s3)
                            if not (s3 in cons): cons.append(s3)

                        cons.pop(i)
                        cons.pop(j)
                        tobreak = True

                        break
                if tobreak: break

        As, bs = [], []
        for i in xrange(len(cons)):
            J = cons[i]
            bs.append(b[J])
            Acol = []
            offset = 0
            for k in xrange(len(ns)):
                Atmp = sparse(A[nl + offset:nl + offset + ns[k]**2, J])
                if len(Atmp.V) == 0:
                    Acol.append(0)
                elif len(Atmp.V) == Atmp[:].size[0]:
                    Acol.append(matrix(Atmp))
                else:
                    Acol.append(Atmp)
                offset += ns[k]**2
            As.append(Acol)

    ms = [len(i) for i in bs]
    bs = matrix(bs)
    meq = L.size[1]

    if (not blockdiagonal) and multiprocess > 1:
        print "Multiprocessing mode can only be used if correlative sparsity is block diagonal. Switching to sequential mode."
        multiprocess = 1

    assert rho > 0 and rho < 2, 'Overrelaxaton parameter (rho) must be (strictly) between 0 and 2'

    # create routine for projecting on { x | L*x = 0 }
    #{ x | L*x = 0 } -> P = I - L*(L.T*L)i *L.T
    LTL = spmatrix([], [], [], (meq, meq))
    offset = 0
    for k in ns:
        Lk = L[offset:offset + k**2, :]
        base.syrk(Lk, LTL, trans='T', beta=1.0)
        offset += k**2
    LTLi = cholmod.symbolic(LTL, amd.order(LTL))
    cholmod.numeric(LTL, LTLi)

    #y = y - L*LTLi*L.T*y
    nssq = sum(matrix([nsk**2 for nsk in ns]))

    def proj(y, ip=True):
        if not ip: y = +y
        tmp = matrix(0.0, size=(meq, 1))

        ypre = +y
        base.gemv(L,y,tmp,trans='T',\
            m = nssq, n = meq, beta = 1)

        cholmod.solve(LTLi, tmp)
        base.gemv(L,tmp,y,beta=1.0,alpha=-1.0,trans='N',\
            m = nssq, n = meq)
        if not ip: return y

    time_to_solve = 0

    #initialize variables
    X = C * 0.0
    Y = +X
    Z = +X
    dualS = +X
    dualy = +b
    PXZ = +X

    proxargs = {
        'C': C,
        'A': As,
        'b': bs,
        'Z': Z,
        'X': X,
        'sigma': sigma,
        'dualS': dualS,
        'dualy': dualy,
        'ns': ns,
        'ms': ms,
        'multiprocess': multiprocess
    }

    if blockdiagonal: proxqp = proxqp_blockdiagonal(proxargs, proxqp)
    else: proxqp = proxqp_general

    if log_cputime: utime = psutil.cpu_times()[0]
    wtime = time.time()
    primal = []
    rpvec, rdvec = [], []
    sigmavec = []
    for it in xrange(maxiter):
        pv, gap = proxqp(proxargs)

        blas.copy(Z, Y)
        blas.axpy(X, Y, alpha=-2.0)
        proj(Y, ip=True)

        #PXZ = sigma*(X-Z)
        blas.copy(X, PXZ)
        blas.scal(sigma, PXZ)
        blas.axpy(Z, PXZ, alpha=-sigma)

        #z = z + rho*(y-x)
        blas.axpy(X, Y, alpha=1.0)
        blas.axpy(Y, Z, alpha=-rho)

        xzn = blas.nrm2(PXZ)
        xn = blas.nrm2(X)
        xyn = blas.nrm2(Y)
        proj(PXZ, ip=True)

        rdual = blas.nrm2(PXZ)
        rpri = sqrt(abs(xyn**2 - rdual**2)) / sigma

        if log_cputime: cputime = psutil.cpu_times()[0] - utime
        else: cputime = 0

        walltime = time.time() - wtime

        if rpri / max(xn, 1.0) < reltol and rdual / max(1.0, xzn) < reltol:
            break

        rpvec.append(rpri / max(xn, 1.0))
        rdvec.append(rdual / max(1.0, xzn))
        primal.append(pv)
        if adaptive:
            if (rdual / xzn * mu < rpri / xn):
                sigmanew = sigma * tau
            elif (rpri / xn * mu < rdual / xzn):
                sigmanew = sigma / tau
            else:
                sigmanew = sigma
            if it % 10 == 0 and it > 0 and tau > 1.0:
                tauscale *= 0.9
                tau = 1 + (tau - 1) * tauscale
            sigma = max(min(sigmanew, 10.0), 0.1)
        sigmavec.append(sigma)
        if verbose:
            if log_cputime:
                print "%d: primal = %e, gap = %e, (rp,rd) = (%e,%e), sigma = %f, (cputime,walltime) = (%f, %f)" % (
                    it, pv, gap, rpri / max(xn, 1.0), rdual / max(1.0, xzn),
                    sigma, cputime, walltime)
            else:
                print "%d: primal = %e, gap = %e, (rp,rd) = (%e,%e), sigma = %f, walltime = %f" % (
                    it, pv, gap, rpri / max(xn, 1.0), rdual / max(1.0, xzn),
                    sigma, walltime)

    sol = {}
    sol['x'] = X
    sol['y'] = Y
    sol['z'] = Z
    sol['cputime'] = cputime
    sol['walltime'] = walltime
    sol['primal'] = primal
    sol['rprimal'] = rpvec
    sol['rdual'] = rdvec
    sol['sigma'] = sigmavec
    return sol
예제 #38
0
    def F(W):

        for j in xrange(N):

            # SVD R[j] = U[j] * diag(sig[j]) * Vt[j]
            lapack.gesvd(+W['r'][j],
                         sv[j],
                         jobu='A',
                         jobvt='A',
                         U=U[j],
                         Vt=Vt[j])

            # Vt[j] := diag(sig[j])^-1 * Vt[j]
            for k in xrange(ns[j]):
                blas.tbsv(sv[j], Vt[j], n=ns[j], k=0, ldA=1, offsetx=k * ns[j])

            # Gamma[j] is an ns[j] x ns[j] symmetric matrix
            #
            #  (sig[j] * sig[j]') ./  sqrt(1 + rho * (sig[j] * sig[j]').^2)

            # S = sig[j] * sig[j]'
            S = matrix(0.0, (ns[j], ns[j]))
            blas.syrk(sv[j], S)
            Gamma[j][:] = div(S, sqrt(1.0 + rho * S**2))[:]
            symmetrize(Gamma[j], ns[j])

            # As represents the scaled mapping
            #
            #     As(x) = A(u * (Gamma .* x) * u')
            #    As'(y) = Gamma .* (u' * A'(y) * u)
            #
            # stored in a similar format as A, except that we use packed
            # storage for the columns of As[i][j].

            for i in xrange(M):

                if (type(A[i][j]) is matrix) or (type(A[i][j]) is spmatrix):

                    # As[i][j][:,k] = vec(
                    #     (U[j]' * mat( A[i][j][:,k] ) * U[j]) .* Gamma[j])

                    copy(A[i][j], As[i][j])
                    As[i][j] = matrix(As[i][j])
                    for k in xrange(ms[i]):
                        cngrnc(U[j],
                               As[i][j],
                               trans='T',
                               offsetx=k * (ns[j]**2),
                               n=ns[j])
                        blas.tbmv(Gamma[j],
                                  As[i][j],
                                  n=ns[j]**2,
                                  k=0,
                                  ldA=1,
                                  offsetx=k * (ns[j]**2))

                    # pack As[i][j] in place
                    #pack_ip(As[i][j], ns[j])
                    for k in xrange(As[i][j].size[1]):
                        tmp = +As[i][j][:, k]
                        misc.pack2(tmp, {'l': 0, 'q': [], 's': [ns[j]]})
                        As[i][j][:, k] = tmp

                else:
                    As[i][j] = 0.0

        # H is an m times m block matrix with i, k block
        #
        #      Hik = sum_j As[i,j]' * As[k,j]
        #
        # of size ms[i] x ms[k].  Hik = 0 if As[i,j] or As[k,j]
        # are zero for all j

        H = spmatrix([], [], [], (sum(ms), sum(ms)))
        rowid = 0
        for i in xrange(M):
            colid = 0
            for k in xrange(i + 1):
                sparse_block = True
                Hik = matrix(0.0, (ms[i], ms[k]))
                for j in xrange(N):
                    if (type(As[i][j]) is matrix) and \
                        (type(As[k][j]) is matrix):
                        sparse_block = False
                        # Hik += As[i,j]' * As[k,j]
                        if i == k:
                            blas.syrk(As[i][j],
                                      Hik,
                                      trans='T',
                                      beta=1.0,
                                      k=ns[j] * (ns[j] + 1) / 2,
                                      ldA=ns[j]**2)
                        else:
                            blas.gemm(As[i][j],
                                      As[k][j],
                                      Hik,
                                      transA='T',
                                      beta=1.0,
                                      k=ns[j] * (ns[j] + 1) / 2,
                                      ldA=ns[j]**2,
                                      ldB=ns[j]**2)
                if not (sparse_block):
                    H[rowid:rowid+ms[i], colid:colid+ms[k]] \
                        = sparse(Hik)
                colid += ms[k]
            rowid += ms[i]

        HF = cholmod.symbolic(H)
        cholmod.numeric(H, HF)

        def solve(x, y, z):
            """
            Returns solution of 

                rho * ux + A'(uy) - r^-T * uz * r^-1 = bx
                A(ux)                                = by
                -ux               - r * uz * r'      = bz.

            On entry, x = bx, y = by, z = bz.
            On exit, x = ux, y = uy, z = uz.
            """

            # bz is a copy of z in the format of x
            blas.copy(z, bz)
            # x := x + rho * bz
            #    = bx + rho * bz
            blas.axpy(bz, x, alpha=rho)

            # x := Gamma .* (u' * x * u)
            #    = Gamma .* (u' * (bx + rho * bz) * u)
            offsetj = 0
            for j in xrange(N):
                cngrnc(U[j], x, trans='T', offsetx=offsetj, n=ns[j])
                blas.tbmv(Gamma[j], x, n=ns[j]**2, k=0, ldA=1, offsetx=offsetj)
                offsetj += ns[j]**2

            # y := y - As(x)
            #   := by - As( Gamma .* u' * (bx + rho * bz) * u)

            blas.copy(x, xp)

            offsetj = 0
            for j in xrange(N):
                misc.pack2(xp, {'l': offsetj, 'q': [], 's': [ns[j]]})
                offsetj += ns[j]**2

            offseti = 0
            for i in xrange(M):
                offsetj = 0
                for j in xrange(N):
                    if type(As[i][j]) is matrix:
                        blas.gemv(As[i][j],
                                  xp,
                                  y,
                                  trans='T',
                                  alpha=-1.0,
                                  beta=1.0,
                                  m=ns[j] * (ns[j] + 1) / 2,
                                  n=ms[i],
                                  ldA=ns[j]**2,
                                  offsetx=offsetj,
                                  offsety=offseti)
                    offsetj += ns[j]**2
                offseti += ms[i]
            # y := -y - A(bz)
            #    = -by - A(bz) + As(Gamma .*  (u' * (bx + rho * bz) * u)

            Af(bz, y, alpha=-1.0, beta=-1.0)

            # y := H^-1 * y
            #    = H^-1 ( -by - A(bz) + As(Gamma.* u'*(bx + rho*bz)*u) )
            #    = uy

            cholmod.solve(HF, y)

            # bz = Vt' * vz * Vt
            #    = uz where
            # vz := Gamma .* ( As'(uy)  - x )
            #     = Gamma .* ( As'(uy)  - Gamma .* (u'*(bx + rho *bz)*u) )
            #     = Gamma.^2 .* ( u' * (A'(uy) - bx - rho * bz) * u ).
            blas.copy(x, xp)

            offsetj = 0
            for j in xrange(N):

                # xp is -x[j] = -Gamma .* (u' * (bx + rho*bz) * u)
                # in packed storage
                misc.pack2(xp, {'l': offsetj, 'q': [], 's': [ns[j]]})
                offsetj += ns[j]**2
            blas.scal(-1.0, xp)

            offsetj = 0
            for j in xrange(N):
                # xp +=  As'(uy)

                offseti = 0
                for i in xrange(M):
                    if type(As[i][j]) is matrix:
                        blas.gemv(As[i][j], y, xp, alpha = 1.0,
                             beta = 1.0, m = ns[j]*(ns[j]+1)/2, \
                                n = ms[i],ldA = ns[j]**2, \
                                offsetx = offseti, offsety = offsetj)
                    offseti += ms[i]

                # bz[j] is xp unpacked and multiplied with Gamma
                #unpack(xp, bz[j], ns[j])

                misc.unpack(xp,
                            bz, {
                                'l': 0,
                                'q': [],
                                's': [ns[j]]
                            },
                            offsetx=offsetj,
                            offsety=offsetj)

                blas.tbmv(Gamma[j],
                          bz,
                          n=ns[j]**2,
                          k=0,
                          ldA=1,
                          offsetx=offsetj)

                # bz = Vt' * bz * Vt
                #    = uz

                cngrnc(Vt[j], bz, trans='T', offsetx=offsetj, n=ns[j])
                symmetrize(bz, ns[j], offset=offsetj)
                offsetj += ns[j]**2

            # x = -bz - r * uz * r'
            blas.copy(z, x)
            blas.copy(bz, z)
            offsetj = 0
            for j in xrange(N):
                cngrnc(+W['r'][j], bz, offsetx=offsetj, n=ns[j])
                offsetj += ns[j]**2
            blas.axpy(bz, x)
            blas.scal(-1.0, x)

        return solve
예제 #39
0
def Fkkt(W):
    """
        Custom solver:

          v := alpha * 2*A'*A * u + beta * v
    """

    global mmS
    mmS = matrix(0.0, (iR, iR))

    global vvV
    vvV = matrix(0.0, (iR, 1))

    # Factor
    #
    #     S = A*D^-1*A' + I
    #
    # where D = 2*D1*D2*(D1+D2)^-1, D1 = d[:n]**2, D2 = d[n:]**2.
    mmAsc = matrix(0.0, (iR, iC))

    d1, d2 = W["di"][:iC] ** 2, W["di"][iC:] ** 2

    # ds is square root of diagonal of D
    ds = sqrt(2.0) * div(mul(W["di"][:iC], W["di"][iC:]), sqrt(d1 + d2))
    d3 = div(d2 - d1, d1 + d2)

    # Asc = A*diag(d)^-1/2
    blas.copy(mmTh, mmAsc)
    for k in range(iR):
        blas.tbsv(ds, mmAsc, n=iC, k=0, ldA=1, incx=iR, offsetx=k)

    # S = I + A * D^-1 * A'
    blas.syrk(mmAsc, mmS)
    mmS[:: iR + 1] += 1.0
    lapack.potrf(mmS)

    def g(x, y, z):

        x[:iC] = 0.5 * (
            x[:iC] - mul(d3, x[iC:]) + mul(d1, z[:iC] + mul(d3, z[:iC])) - mul(d2, z[iC:] - mul(d3, z[iC:]))
        )
        x[:iC] = div(x[:iC], ds)

        # Solve
        #
        #     S * v = 0.5 * A * D^-1 * ( bx[:n]
        #             - (D2-D1)*(D1+D2)^-1 * bx[n:]
        #             + D1 * ( I + (D2-D1)*(D1+D2)^-1 ) * bz[:n]
        #             - D2 * ( I - (D2-D1)*(D1+D2)^-1 ) * bz[n:] )

        blas.gemv(mmAsc, x, vvV)
        lapack.potrs(mmS, vvV)

        # x[:n] = D^-1 * ( rhs - A'*v ).
        blas.gemv(mmAsc, vvV, x, alpha=-1.0, beta=1.0, trans="T")
        x[:iC] = div(x[:iC], ds)

        # x[n:] = (D1+D2)^-1 * ( bx[n:] - D1*bz[:n]  - D2*bz[n:] )
        #         - (D2-D1)*(D1+D2)^-1 * x[:n]
        x[iC:] = div(x[iC:] - mul(d1, z[:iC]) - mul(d2, z[iC:]), d1 + d2) - mul(d3, x[:iC])

        # z[:n] = D1^1/2 * (  x[:n] - x[n:] - bz[:n] )
        # z[n:] = D2^1/2 * ( -x[:n] - x[n:] - bz[n:] ).
        z[:iC] = mul(W["di"][:iC], x[:iC] - x[iC:] - z[:iC])
        z[iC:] = mul(W["di"][iC:], -x[:iC] - x[iC:] - z[iC:])

    return g