Example #1
0
def mfem_smoother(name, **kwargs):
    prc = kwargs.pop('prc')
    blockname = kwargs.pop('blockname')
    row = prc.get_row_by_name(blockname)
    col = prc.get_col_by_name(blockname)
    mat = prc.get_operator_block(row, col)

    if isinstance(mat, mfem.ComplexOperator):
        conv = mat.GetConvention()

        blockOffsets = mfem.intArray()
        blockOffsets.SetSize(3)
        blockOffsets[0] = 0
        blockOffsets[1] = mat.Height() // 2
        blockOffsets[2] = mat.Height() // 2
        blockOffsets.PartialSum()

        smoother = mfem.BlockDiagonalPreconditioner(blockOffsets)

        m_r = mat._real_operator
        #m_i = mat._imag_operator
        pc_r = _create_smoother(name, m_r)
        pc_i = mfem.ScaledOperator(
            pc_r, 1 if conv == mfem.ComplexOperator.HERMITIAN else -1)

        smoother.SetDiagonalBlock(0, pc_r)
        smoother.SetDiagonalBlock(1, pc_i)
        smoother._smoothers = (pc_r, pc_i)

    else:
        smoother = _create_smoother(name, mat)
    return smoother
Example #2
0
#        [ S0^{-1}     0     ]
#        [   0     Shat^{-1} ]      Shat = (Bhat^T Sinv Bhat)
#
#     corresponding to the primal (x0) and interfacial (xhat) unknowns.
#     Since the Shat operator is equivalent to an H(div) matrix reduced to
#     the interfacial skeleton, we approximate its inverse with one V-cycle
#     of the ADS preconditioner from the hypre library (in 2D we use AMS for
#     the rotated H(curl) problem).
S0inv = mfem.HypreBoomerAMG(matS0)
S0inv.SetPrintLevel(0)

Shat = mfem.RAP(matSinv, matBhat)
if (dim == 2): Shatinv = mfem.HypreAMS(Shat, xhat_space)
else: Shatinv = mfem.HypreADS(Shat, xhat_space)

P = mfem.BlockDiagonalPreconditioner(true_offsets)
P.SetDiagonalBlock(0, S0inv)
P.SetDiagonalBlock(1, Shatinv)

# 12. Solve the normal equation system using the PCG iterative solver.
#     Check the weighted norm of residual for the DPG least square problem.
#     Wrap the primal variable in a GridFunction for visualization purposes.
pcg = mfem.CGSolver(MPI.COMM_WORLD)
pcg.SetOperator(A)
pcg.SetPreconditioner(P)
pcg.SetRelTol(1e-6)
pcg.SetMaxIter(200)
pcg.SetPrintLevel(1)
pcg.Mult(b, x)

LSres = mfem.HypreParVector(test_space)
Example #3
0
#M2 = M.Transpose()
#M3 = M2.Transpose()
MinvBt = B.Transpose()
Md = mfem.HypreParVector(MPI.COMM_WORLD, M.GetGlobalNumRows(),
                         M.GetRowStarts())
M.GetDiag(Md)
MinvBt.InvScaleRows(Md)
S = mfem.hypre.ParMult(B, MinvBt)

invM = mfem.HypreDiagScale(M)
invS = mfem.HypreBoomerAMG(S)
invM.iterative_mode = False
invS.iterative_mode = False

darcyPr = mfem.BlockDiagonalPreconditioner(block_trueOffsets)
darcyPr.SetDiagonalBlock(0, invM)
darcyPr.SetDiagonalBlock(1, invS)

maxIter = 500
rtol = 1e-6
atol = 1e-10

import time
stime = time.clock()
solver = mfem.MINRESSolver(MPI.COMM_WORLD)

solver.SetAbsTol(atol)
solver.SetRelTol(rtol)
solver.SetMaxIter(maxIter)
solver.SetOperator(darcyOp)
Example #4
0
def genearate_smoother(engine, level, blk_opr):
    from petram.engine import ParallelEngine
    assert not isinstance(
        engine, ParallelEngine), "Parallel is not supported"

    engine.access_idx = 0
    P = None
    diags = []
    cols = [0]
    ess_tdofs = []
    A, _X, _RHS, _Ae,  _B,  _M, _dep_vars = engine.assembled_blocks
    widths = A.get_local_col_widths()

    use_complex_opr = A.complex and (A.shape[0] == blk_opr.NumRowBlocks())

    for dep_var in engine.r_dep_vars:
        offset = engine.r_dep_var_offset(dep_var)

        tmp_cols = []
        tmp_diags = []
        if engine.r_isFESvar(dep_var):
            ess_tdof = mfem.intArray(engine.ess_tdofs[dep_var])
            ess_tdofs.append(ess_tdofs)
            opr = A[offset, offset]

            if use_complex_opr:
                mat = blk_opr._linked_op[(offset, offset)]
                conv = mat.GetConvention()
                conv == 1 if mfem.ComplexOperator.HERMITIAN else -1
                mat1 = mat._real_operator
                mat2 = mat._imag_operator
            else:
                conv = 1
                if A.complex:
                    mat1 = blk_opr.GetBlock(offset*2, offset*2)
                    mat2 = blk_opr.GetBlock(offset*2 + 1, offset*2 + 1)
                else:
                    mat1 = blk_opr.GetBlock(offset, offset)

            if A.complex:
                dd = opr.diagonal()
                diag = mfem.Vector(list(dd.real))
                print("real", dd.real)
                rsmoother = mfem.OperatorChebyshevSmoother(mat1,
                                                           diag,
                                                           ess_tdof,
                                                           2)
                dd = opr.diagonal()*conv
                diag = mfem.Vector(list(dd.real))
                print("imag", dd.imag)
                ismoother = mfem.OperatorChebyshevSmoother(mat1,
                                                           diag,
                                                           ess_tdof,
                                                           2)
                tmp_cols.append(opr.shape[0])
                tmp_cols.append(opr.shape[0])
                tmp_diags.append(rsmoother)
                tmp_diags.append(ismoother)

            else:
                dd = opr.diagonal()
                diag = mfem.Vector(list(dd))
                smoother = mfem.OperatorChebyshevSmoother(mat1,
                                                          diag,
                                                          ess_tdof,
                                                          2)
                tmp_diags.append(smoother)
                tmp_cols.append(opr.shape[0])

        else:
            print("Non FESvar", dep_var, offset)
            tmp_cols.append(widths[offset])
            tmp_diags.append(mfem.IdentityOperator(widths[offset]))
            if A.complex:
                tmp_cols.append(widths[offset])
                oo = mfem.IdentityOperator(widths[offset])
                if conv == -1:
                    oo2 = mfem.ScaleOperator(oo, -1)
                    oo2._opr = oo
                    tmp_diags.append(oo2)
                else:
                    tmp_diags.append(oo)

        if use_complex_opr:
            tmp_cols = [0] + tmp_cols
            blockOffsets = mfem.intArray(tmp_cols)
            blockOffsets.PartialSum()
            smoother = mfem.BlockDiagonalPreconditioner(blockOffsets)
            smoother.SetDiagonalBlock(0, tmp_diags[0])
            smoother.SetDiagonalBlock(1, tmp_diags[1])
            smoother._smoother = tmp_diags
            cols.append(tmp_cols[1]*2)
            diags.append(smoother)
        else:
            cols.extend(tmp_cols)
            diags.extend(tmp_diags)

    co = mfem.intArray(cols)
    co.PartialSum()

    P = mfem.BlockDiagonalPreconditioner(co)
    for i, d in enumerate(diags):
        P.SetDiagonalBlock(i,  d)
    P._diags = diags
    P._ess_tdofs = ess_tdofs
    return P
Example #5
0
    def solve_serial(self, A, b, x=None):
        def get_block(Op, i, j):
            try:
                return Op._linked_op[(i, j)]
            except KeyError:
                return None

        offset = A.RowOffsets()
        rows = A.NumRowBlocks()
        cols = A.NumColBlocks()
        if self.gui.write_mat:
            for i in range(cols):
                for j in range(rows):
                    m = get_block(A, i, j)
                    if m is None: continue
                    m.Print('matrix_' + str(i) + '_' + str(j))
            for i, bb in enumerate(b):
                for j in range(rows):
                    v = bb.GetBlock(j)
                    v.Print('rhs_' + str(i) + '_' + str(j))

        M = mfem.BlockDiagonalPreconditioner(offset)

        prcs = dict(self.gui.preconditioners)
        name = self.Aname
        assert not self.gui.parent.is_complex(), "can not solve complex"
        if self.gui.parent.is_converted_from_complex():
            name = sum([[n, n] for n in name], [])
        '''   
        this if block does a generalized version of this...
        M1 = mfem.GSSmoother(get_block(A, 0, 0))
        M1.iterative_mode = False
        M.SetDiagonalBlock(0, M1)
        '''
        for k, n in enumerate(name):

            prc = prcs[n][0]
            if prc == "None": continue
            name = "".join([tmp for tmp in prc if not tmp.isdigit()])
            A0 = get_block(A, k, k)
            cls = SparseSmootherCls[name][0]
            arg = SparseSmootherCls[name][1]
            if name == 'MUMPS':
                invA0 = cls(A0, gui=self.gui[prc], engine=self.engine)
            else:
                invA0 = cls(A0, arg)
            invA0.iterative_mode = False
            M.SetDiagonalBlock(k, invA0)
        '''
        We should support Shur complement type preconditioner
        if offset.Size() > 2:
            B =  get_block(A, 1, 0)
            MinvBt = get_block(A, 0, 1)
            Md = mfem.Vector(get_block(A, 0, 0).Height())
            get_block(A, 0, 0).GetDiag(Md)
            for i in range(Md.Size()):
                if Md[i] != 0.:
                    MinvBt.ScaleRow(i, 1/Md[i])
                else:
                    assert False, "diagnal element of matrix is zero"
            S = mfem.Mult(B, MinvBt)
            S.iterative_mode = False
            SS = mfem.DSmoother(S)
            SS.iterative_mode = False            
            M.SetDiagonalBlock(1, SS)
        '''
        '''
        int GMRES(const Operator &A, Vector &x, const Vector &b, Solver &M,
          int &max_iter, int m, double &tol, double atol, int printit)
        '''
        maxiter = int(self.maxiter)
        atol = self.abstol
        rtol = self.reltol
        kdim = int(self.kdim)
        printit = 1

        sol = []

        solver = mfem.GMRESSolver()
        solver.SetKDim(kdim)
        #solver = mfem.MINRESSolver()
        solver.SetAbsTol(atol)
        solver.SetRelTol(rtol)
        solver.SetMaxIter(maxiter)

        solver.SetOperator(A)
        solver.SetPreconditioner(M)
        solver.SetPrintLevel(1)

        for bb in b:
            if x is None:
                xx = mfem.Vector(bb.Size())
                xx.Assign(0.0)
            else:
                xx = x
                #for j in range(cols):
                #   print x.GetBlock(j).Size()
                #   print x.GetBlock(j).GetDataArray()
                #assert False, "must implement this"
            solver.Mult(bb, xx)
            sol.append(xx.GetDataArray().copy())
        sol = np.transpose(np.vstack(sol))
        return sol
Example #6
0
    def solve_parallel(self, A, b, x=None):
        from mpi4py import MPI
        myid = MPI.COMM_WORLD.rank
        nproc = MPI.COMM_WORLD.size
        from petram.helper.mpi_recipes import gather_vector

        def get_block(Op, i, j):
            try:
                return Op._linked_op[(i, j)]
            except KeyError:
                return None

        offset = A.RowOffsets()
        rows = A.NumRowBlocks()
        cols = A.NumColBlocks()

        if self.gui.write_mat:
            for i in range(cols):
                for j in range(rows):
                    m = get_block(A, i, j)
                    if m is None: continue
                    m.Print('matrix_' + str(i) + '_' + str(j))
            for i, bb in enumerate(b):
                for j in range(rows):
                    v = bb.GetBlock(j)
                    v.Print('rhs_' + str(i) + '_' + str(j) + '.' + smyid)
            if x is not None:
                for j in range(rows):
                    xx = x.GetBlock(j)
                    xx.Print('x_' + str(i) + '_' + str(j) + '.' + smyid)

        M = mfem.BlockDiagonalPreconditioner(offset)

        prcs = dict(self.gui.preconditioners)
        name = self.Aname
        assert not self.gui.parent.is_complex(), "can not solve complex"
        if self.gui.parent.is_converted_from_complex():
            name = sum([[n, n] for n in name], [])

        for k, n in enumerate(name):
            prc = prcs[n][1]
            if prc == "None": continue
            name = "".join([tmp for tmp in prc if not tmp.isdigit()])

            A0 = get_block(A, k, k)
            if A0 is None and not name.startswith('schur'): continue

            if hasattr(mfem.HypreSmoother, prc):
                invA0 = mfem.HypreSmoother(A0)
                invA0.SetType(getattr(mfem.HypreSmoother, prc))
            elif prc == 'ams':
                depvar = self.engine.r_dep_vars[k]
                dprint1("setting up AMS for ", depvar)
                prec_fespace = self.engine.fespaces[depvar]
                invA0 = mfem.HypreAMS(A0, prec_fespace)
                invA0.SetSingularProblem()
            elif name == 'MUMPS':
                cls = SparseSmootherCls[name][0]
                invA0 = cls(A0, gui=self.gui[prc], engine=self.engine)
            elif name.startswith('schur'):
                args = name.split("(")[-1].split(")")[0].split(",")
                dprint1("setting up schur for ", args)
                if len(args) > 1:
                    assert False, "not yet supported"
                for arg in args:
                    r1 = self.engine.dep_var_offset(arg.strip())
                    c1 = self.engine.r_dep_var_offset(arg.strip())
                    B = get_block(A, k, c1)
                    Bt = get_block(A, r1, k).Transpose()
                    Bt = Bt.Transpose()
                    B0 = get_block(A, r1, c1)
                    Md = mfem.HypreParVector(MPI.COMM_WORLD,
                                             B0.GetGlobalNumRows(),
                                             B0.GetColStarts())
                    B0.GetDiag(Md)
                    Bt.InvScaleRows(Md)
                    S = mfem.ParMult(B, Bt)
                    invA0 = mfem.HypreBoomerAMG(S)
                    invA0.iterative_mode = False
            else:
                cls = SparseSmootherCls[name][0]
                invA0 = cls(A0, gui=self.gui[prc])

            invA0.iterative_mode = False
            M.SetDiagonalBlock(k, invA0)
        '''
        We should support Shur complement type preconditioner
        if offset.Size() > 2:
            B =  get_block(A, 1, 0)
            MinvBt = get_block(A, 0, 1)
            #Md = mfem.HypreParVector(MPI.COMM_WORLD,
            #                        A0.GetGlobalNumRows(),
            #                        A0.GetRowStarts())
            Md = mfem.Vector()
            A0.GetDiag(Md)
            MinvBt.InvScaleRows(Md)
            S = mfem.ParMult(B, MinvBt)
            invS = mfem.HypreBoomerAMG(S)
            invS.iterative_mode = False
            M.SetDiagonalBlock(1, invS)
        '''
        maxiter = int(self.maxiter)
        atol = self.abstol
        rtol = self.reltol
        kdim = int(self.kdim)
        printit = 1

        sol = []

        solver = mfem.GMRESSolver(MPI.COMM_WORLD)
        solver.SetKDim(kdim)

        #solver = mfem.MINRESSolver(MPI.COMM_WORLD)
        #solver.SetOperator(A)

        #solver = mfem.CGSolver(MPI.COMM_WORLD)
        solver.SetOperator(A)
        solver.SetAbsTol(atol)
        solver.SetRelTol(rtol)
        solver.SetMaxIter(maxiter)
        solver.SetPreconditioner(M)
        solver.SetPrintLevel(1)

        # solve the problem and gather solution to head node...
        # may not be the best approach

        for bb in b:
            rows = MPI.COMM_WORLD.allgather(np.int32(bb.Size()))
            rowstarts = np.hstack((0, np.cumsum(rows)))
            dprint1("rowstarts/offser", rowstarts, offset.ToList())
            if x is None:
                xx = mfem.BlockVector(offset)
                xx.Assign(0.0)
            else:
                xx = x
                #for j in range(cols):
                #   dprint1(x.GetBlock(j).Size())
                #   dprint1(x.GetBlock(j).GetDataArray())
                #assert False, "must implement this"
            solver.Mult(bb, xx)
            s = []
            for i in range(offset.Size() - 1):
                v = xx.GetBlock(i).GetDataArray()
                vv = gather_vector(v)
                if myid == 0:
                    s.append(vv)
                else:
                    pass
            if myid == 0:
                sol.append(np.hstack(s))
        if myid == 0:
            sol = np.transpose(np.vstack(sol))
            return sol
        else:
            return None
 def __call__(self, *args, **kwargs):
     offset = self.opr.RowOffsets()
     D = mfem.BlockDiagonalPreconditioner(offset)
     if self.func is not None:
         self.func(D, self, *args, **kwargs)
     return D