Exemplo n.º 1
0
def go_back(x,y,a=40,b=50,R_0 = 90,l=10,m=3,aa=0.0,q0=3.0,eps=.07):

    hit_divert = (x>b)
    inCORE = x<b
    stopevolve = hit_divert
    
    #eps = .2
    C = ((2*m*l*a**2)/(R_0*q0*b**2))*eps
    
    def func(y_out):
        return (-y + y_out - C*(x/b)**(m-2) *np.cos(m*y_out))**2
    
    def func2(y_out):
        return (-y_old + y_out + (2.0*np.pi/q) + aa*np.cos(y_out))**2
    
    y_old = copy(y)
    y_old = (newton_krylov(func,y))
    y_old = np.mod(y_old,2.0*np.pi)

    x_old = x + (m*b*C)/(m-1)*(x/b)**(m-1) *np.sin(m*y_old)

    q = q0*(x_old/a)**2

    y_old2 = copy(y_old)
    y_old2 = (newton_krylov(func2,y_old))

    #y_old2 = y_old - 2*np.pi/q #- aa*np.cos(
    y_old2 = np.mod(y_old2,2.0*np.pi)
    x_old2 = x_old*(1.0 -aa*np.sin(y_old2))



    return x_old2,y_old2
    def do_one_step(self, t, psi0, x0):
        """
        Take one integration step.
        
        """

        # Apply adjoint method
        f = lambda y: self.residue_adjoint(y, psi0, x0)
        b0 = so.newton_krylov(f, self.b, f_tol=1e-14)
        U0 = cayley_klein(self.half_time * b0)
        psi1 = apply_2by2(U0, psi0)
        x1 = hopf(psi1)

        # Apply direct method
        f = lambda y: self.residue_direct(y, psi1, x1)
        b1 = so.newton_krylov(f, b0, f_tol=1e-14)
        U1 = cayley_klein(self.half_time * b1)
        psi2 = apply_2by2(U1, psi1)
        x2 = hopf(psi2)

        self.b = b1

        # Compute momentum map, if needed
        m = None
        if self.compute_momentum:
            m = self.compute_momentum_map_S3(psi0, psi1)

        return psi2, x2, m
    def do_one_step(self, t, psi0, x0):

        callback = None
        if self.diagnostics:
            callback = self.diagnostics_logger

        f = lambda y: self.residue_mu_direct(y, psi0, x0)
        self.b = so.newton_krylov(f, self.b, f_tol=1e-14, 
                                  callback=callback, verbose=False)
        U = cayley_klein(self.half_time*self.b)
        psi0 = apply_2by2(U, psi0)
        x0 = hopf(psi0)

        self.diagnostics_logger.store()

        f = lambda y: self.residue_mu_adjoint(y, psi0, x0)
        self.b = so.newton_krylov(f, self.b, f_tol=1e-14, 
                                  callback=callback, verbose=False)
        U = cayley_klein(self.half_time * self.b)
        psi0 = apply_2by2(U, psi0)
        x0 = hopf(psi0)

        self.diagnostics_logger.store()

        return psi0, x0
Exemplo n.º 4
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    def do_step(self, t, dt, uold, j=None):
        for i in range(self.stages):
            temp = uold + dt * sum(
                [self.A[i, m] * self.k[m] for m in range(i)])
            try:
                self.k[i] = newton_krylov(f_root(t, dt, temp, self.rhs,
                                                 self.A[i, i], self.c[i]),
                                          uold if i == 0 else self.k[i - 1],
                                          f_tol=1.e-10,
                                          f_rtol=1.e-10)
            except ValueError:
                self.k[i] = newton_krylov(f_root(t, dt, temp, self.rhs,
                                                 self.A[i, i], self.c[i]),
                                          uold,
                                          f_tol=1.e-10,
                                          f_rtol=1.e-10)

        unew = uold + dt * sum(
            [self.b[i] * self.k[i] for i in range(self.stages)])
        ulow = uold + dt * sum(
            [self.b_hat[i] * self.k[i] for i in range(self.stages)])

        if j is not None:
            j_up, j_quad_est = self.do_quadrature(t, uold, dt, j, 1)
            return unew, unew - ulow, j_up, j_quad_est

        return unew, unew - ulow
Exemplo n.º 5
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        def solve(self):
            
            self.time,self.u = self.dydt.createArray()
            print('Running Adams-Moulton (Implicit) 5th-ord')
            
            ## compute first fourth points using 4th order (classic) Runge Kutta

            for i in range(4):  
                # using Backward Euler for the first point     
                func = lambda up1 : up1 - self.u[i]-self.dt*self.f(self.time[i+1], up1) 
                self.u[i+1] = newton_krylov(func , self.u[i] , f_tol = 10e-8) 

            #for i in range(4):  
            #    k1 = self.dydt.f(self.time[i],self.u[i])
            #    k2 = self.dydt.f(self.time[i]+self.dt/2. , self.u[i]+ self.dt/2. *k1 )
            #    k3 = self.dydt.f(self.time[i]+self.dt/2. , self.u[i]+ self.dt/2. *k2 )
            #    k4 = self.dydt.f(self.time[i]+self.dt    , self.u[i]+ self.dt    *k3 )

            #    self.u[i+1] = self.u[i] + self.dt/6. * (k1 + 2*k2 + 2*k3 + k4)





            for i in range(4, len(self.time)-1):
                
                    
                function = lambda up1 : - up1 + self.u[i] + self.dt/720. * ( 251. * self.f(self.time[i+1],up1) \
                                                      + 646. * self.f(self.time[i],self.u[i])\
                                                      - 264. * self.f(self.time[i-1],self.u[i-1])\
                                                      + 106. * self.f(self.time[i-2],self.u[i-2])\
                                                      -  19. * self.f(self.time[i-3],self.u[i-3]))
                    
                self.u[i+1] =  newton_krylov(function , self.u[i] , f_tol = 10e-12) 
                
            print('... Done!')
            AdamsMoulton5th.solved = True

            if self.file != None:
                super().write2file()
           
            if self.save:
                return self.time,self.u
            
            def plot(self):
               if AdamsMoulton5th.solved:
                  super().plot('Sys ODE solution using Adams-Moulton 5th order','time [s]','y(t)')
               else:
                  print("Unsolved problem, call `solve` method before")
    def do_one_step(self, t, X0):

        rho0 = vector_hatmap(X0, self.gamma)
        grad = self.gradient_hamiltonian(rho0)

        callback = None
        if self.diagnostics:
            callback = self.diagnostics_logger

        def optimization_function(rho1):
            s = grad + self.gradient_hamiltonian(rho1)
            res  = np.empty((self.N, 3, 3))
            for n in range(0, self.N):               
                #g = linalg.expm(-self.h/2*s[n, :, :])
                g = cayley(-self.h/4*s[n, :, :]).squeeze()
                

                res[n, :, :] = rho1[n, :, :] - Ad(g, rho0[n, :, :])
            return res


        #d = Diagnostics()

        rho1 = newton_krylov(optimization_function, rho0, f_tol=1e-14, callback=callback)
        self.diagnostics_logger.store()


        #print d.n_current


        return vector_invhat(rho1, self.gamma)
Exemplo n.º 7
0
def hidalgo_initial_guess(w, dtgaps):
    """ Returns the initial guess found in DOI: 10.1007/s10915-010-9426-6
        NB: Only implemented in 1D
    """
    dx = dxi[0]
    q = zeros([N + 1] * (ndim + 1) + [n])
    qj = w  # Set values at start of time step to WENO reconstruction
    for j in range(N + 1):  # Loop over the time levels in the DG predictor
        dt = dtgaps[j]
        dqdxj = dot(derivs, qj)

        for i in range(N + 1):  # Loop over spatial nodes at time level j
            qij = qj[i]
            dqdxij = dqdxj[i]
            J = dot(jacobian(qij, 0), dqdxij)
            Sj = source(qij)

            if superStiff:  # If sources are very stiff, root must be found implicitly
                f = lambda X: X - qij + dt / dx * J - dt / 2 * (Sj + source(X))
                q[j, i] = newton_krylov(f, qij, f_tol=TOL)
            else:
                q[j, i] = qij - dt / dx * J + dt * Sj

        qj = q[j]

    return q.reshape([NT, n])
Exemplo n.º 8
0
Arquivo: model.py Projeto: KikeM/pybem
    def compute_inflow_angle(self, r, phi0=0.0):
        """Solve nonlinear inflow angle equation.

        Parameters
        ----------
        r: float
            r / D parameter

        x0: float
            Initial condition

        Returns
        -------
        float
            If NO convergence, returns np.nan
        """

        # Fix section
        func = partial(self._residual, r=r)

        # try:
        phi = newton_krylov(func, phi0)
        # except Exception as ex:
        #     print(ex)
        #     phi = np.array(np.nan)

        return phi.item()
Exemplo n.º 9
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def solve(preconditioning=True):
    """Compute the solution"""
    count = [0]

    def residual(P):
        count[0] += 1

        d2x = zeros_like(P)
        d2y = zeros_like(P)

        d2x[1:-1] = (P[2:] - 2 * P[1:-1] + P[:-2]) / hx / hx
        d2x[0] = (P[1] - 2 * P[0] + P_left) / hx / hx
        d2x[-1] = (P_right - 2 * P[-1] + P[-2]) / hx / hx

        d2y[:, 1:-1] = (P[:, 2:] - 2 * P[:, 1:-1] + P[:, :-2]) / hy / hy
        d2y[:, 0] = (P[:, 1] - 2 * P[:, 0] + P_bottom) / hy / hy
        d2y[:, -1] = (P_top - 2 * P[:, -1] + P[:, -2]) / hy / hy

        return d2x + d2y + 5 * cosh(P).mean()**2

    # preconditioner
    if preconditioning:
        M = get_preconditioner()
    else:
        M = None

    # solve
    guess = zeros((nx, ny), float)

    sol = newton_krylov(residual, guess, verbose=1, inner_M=M)
    print 'Residual', abs(residual(sol)).max()
    print 'Evaluations', count[0]

    return sol
Exemplo n.º 10
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    def root_find(self, w, Ww, dt, dX):
        """ Finds DG coefficients with Newton-Krylov, if iteration has failed
        """
        q = self.initial_guess(self, w, dt, dX)

        def f(x): return dot(self.DG_U, x) - self.rhs(x, Ww, dt, dX)
        return newton_krylov(f, q, f_tol=self.tol, method='bicgstab')
Exemplo n.º 11
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    def find_best_rotation_parameters(self, xi: np.ndarray, c: np.ndarray,
                                      session: tf.Session):
        guess = self._find_rotation_matrix_guess(xi, c, session)

        def loss_function(angles: np.ndarray):
            mr = session.run([self.RTM],
                             feed_dict={
                                 self.xi_input: xi,
                                 self.c: c,
                                 self.angles: angles
                             })[0]

            mr = mr[:, 0, :]

            return np.array([
                mr[0, 1] - mr[1, 0], mr[0, 2] - mr[2, 0], mr[2, 1] - mr[1, 2]
            ])

        try:
            sol = newton_krylov(loss_function,
                                guess,
                                method='lgmres',
                                verbose=0)
        except NoConvergence:
            return None
        return sol
Exemplo n.º 12
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def go_forward(x,y,a=40,b=50,R_0 = 90,l=10,m=3,aa=0.0,q0=3.0):

    hit_divert = (x>b)
    inCORE = x<b
    stopevolve = hit_divert
    
    eps = .2
    C = ((2*m*l*a**2)/(R_0*q0*b**2))*eps

    x_new = x/(1-aa*np.sin(y))
    q = q0*(x_new/a)**2
    y_new =  (y+ 2*np.pi/q + aa*np.cos(y))
    y_new = np.mod(y_new,2*np.pi)

    def func(x_out):
        return (-x_new + x_out +(m*b*C)/(m-1)*(x_out/b)**(m-1) *np.sin(m*y_new))**2
    
    x_new2 = (newton_krylov(func,x_new,method='gmres',maxiter=50))
    y_new2 = (y_new - C*(x_new2/b)**(m-2) * np.cos(m*y_new))
                                
    #print 'xchange:', x_new2/x

    x_new = x_new2
    y_new = np.mod(y_new2,2*np.pi)

    
    return x_new,y_new
Exemplo n.º 13
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    def cn_implicit_builtin_solver(self, iterations=None):
        if iterations == None:
            iterations = self.N
        self.sol[0, :] = self.initial(self.xi)
        A_const = self.tridiag(self.r / 2, 1.0j - self.r, self.r / 2, self.M)
        B_const = self.tridiag(-self.r / 2, 1.0j + self.r, -self.r / 2, self.M)
        A_const[0, -1] = self.r / 2
        A_const[-1, 0] = self.r / 2
        B_const[0, -1] = -self.r / 2
        B_const[-1, 0] = -self.r / 2

        for i in range(0, iterations):
            abs_prev = np.absolute(self.sol[i, 0:-1])
            B = 0.5 * self.lmbda * self.k * np.diag(abs_prev**2 + 0.0j, 0)
            B += B_const
            b = np.matmul(B, self.sol[i, 0:-1])

            def F(U):
                folded_U = U[0:self.M] + 1.0j * U[self.M:]
                abs_next = np.absolute(folded_U)
                A = -0.5 * self.lmbda * self.k * np.diag(abs_next**2 + 0.0j, 0)
                A += A_const
                a = np.matmul(A, folded_U)
                return np.concatenate((np.real(a - b), np.imag(a - b)), axis=0)

            unfolded_U = np.concatenate(
                (np.real(self.sol[i, 0:-1]), np.imag(self.sol[i, 0:-1])),
                axis=0)
            opt = optimize.newton_krylov(F, unfolded_U, f_tol=1e-7)
            self.sol[i + 1,
                     0:-1] = opt[0:self.M] + 1.0j * np.real(opt[self.M:])
        self.sol[:, -1] = self.sol[:, 0]
        return 0
def solve(preconditioning=True):
    """Compute the solution"""
    count = [0]

    def residual(P):
        count[0] += 1

        d2x = zeros_like(P)
        d2y = zeros_like(P)

        d2x[1:-1] = (P[2:] - 2 * P[1:-1] + P[:-2]) / hx / hx
        d2x[0] = (P[1] - 2 * P[0] + P_left) / hx / hx
        d2x[-1] = (P_right - 2 * P[-1] + P[-2]) / hx / hx

        d2y[:, 1:-1] = (P[:, 2:] - 2 * P[:, 1:-1] + P[:, :-2]) / hy / hy
        d2y[:, 0] = (P[:, 1] - 2 * P[:, 0] + P_bottom) / hy / hy
        d2y[:, -1] = (P_top - 2 * P[:, -1] + P[:, -2]) / hy / hy

        return d2x + d2y + 5 * cosh(P).mean() ** 2

    # preconditioner
    if preconditioning:
        M = get_preconditioner()
    else:
        M = None

    # solve
    guess = zeros((nx, ny), float)

    sol = newton_krylov(residual, guess, verbose=1, inner_M=M)
    print "Residual", abs(residual(sol)).max()
    print "Evaluations", count[0]

    return sol
Exemplo n.º 15
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def advanceSolImplicit_NK(main, MZ, eqns):
    old = np.zeros(np.shape(main.a0))
    old[:] = main.a0[:]
    main.a0[:] = main.a.a[:]
    main.getRHS(main, eqns)
    R0 = np.zeros(np.shape(main.RHS))
    R0[:] = main.RHS[:]

    def unsteadyResid(v):
        main.a.a[:] = np.reshape(v, np.shape(main.a.a))
        main.getRHS(main, eqns)
        R1 = np.zeros(np.shape(main.RHS))
        R1[:] = main.RHS[:]
        Resid = (v - main.a0.flatten()) - 0.5 * main.dt * (R0 + R1).flatten()
        return Resid

    def printnorm(x, r):
        ## Create Global residual
        data = main.comm.gather(np.linalg.norm(r)**2, root=0)
        if (main.mpi_rank == 0):
            Rstar_glob = 0.
            for j in range(0, main.num_processes):
                Rstar_glob += data[j]
            Rstar_glob = np.sqrt(Rstar_glob)
            for j in range(1, main.num_processes):
                main.comm.send(Rstar_glob, dest=j)
        else:
            Rstar_glob = main.comm.recv(source=0)
        if (Rstar_glob < 1e-9):
            if (main.mpi_rank == 0):
                print('Convergence Achieved, NL norm = ' +
                      str(np.linalg.norm(Rstar_glob)))
            r[:] = 1e-100
        else:
            if (main.mpi_rank == 0):
                print('NL norm = ' + str(np.linalg.norm(Rstar_glob)))

    #jac = BroydenFirst()
    #kjac = KrylovJacobian(inner_M=InverseJacobian(jac))
    sol = newton_krylov(unsteadyResid,
                        main.a.a.flatten(),
                        iter=None,
                        rdiff=None,
                        method='gmres',
                        inner_maxiter=40,
                        inner_M=None,
                        outer_k=10,
                        verbose=4,
                        maxiter=None,
                        f_tol=1e-8,
                        f_rtol=1e-8,
                        x_tol=None,
                        x_rtol=None,
                        tol_norm=None,
                        line_search='armijo',
                        callback=printnorm)
    main.a.a = np.reshape(sol, np.shape(main.a.a))
    main.a0[:] = np.reshape(sol, np.shape(main.a.a))
    main.t += main.dt
    main.iteration += 1
Exemplo n.º 16
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 def solve(self):
   x_fp = newton_krylov(self.rootOperator, self.x_0, maxiter = self.numberOfIterations, verbose=0, x_rtol=self.convergenceCriterion, method='lgmres', callback=self.iterationCounter)
   print "scipy Newton Krylov converged after" , self.iterationStep, "steps"
   #As a side effect, we calculate other intersting physical quantities based on the found fixpoint solution
   self.derivePhysicalQuantitiesFromFixpoint(x_fp)
   #Reset iteration counter in case solve is called various times (and class is not re-instantiated)
   self.iterationStep = 0     
Exemplo n.º 17
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 def M_main(self, z):  #Main progenitor halo mass from Neistein 2006
     M_0 = np.power(10, self.logM0)
     gamma = self.omega_m * self.h * np.exp(
         -self.omega_b * (1 + np.sqrt(2 * self.h) / self.omega_m))
     return np.log10(
         self.omega_m / (gamma**3) *
         newton_krylov(self.F_inv1(z, self.z_0, M_0, gamma), 0.01))
Exemplo n.º 18
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 def implicit_solve(self, next_x, func, method="unused", **kwargs):
     """A solver for the implicit equations.
     """
     assert_is_instance(next_x, np.ndarray, descriptor="Initial Guess", checking_obj=self)
     assert_is_callable(func, descriptor="Function of RHS for Implicit Solver", checking_obj=self)
     sol = scop.newton_krylov(func, next_x.reshape(-1))
     assert_is_instance(sol, np.ndarray, descriptor="Solution", checking_obj=self)
     return sol.reshape(self.dim_for_time_solver)
Exemplo n.º 19
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def Question1():
    t0 = time()
    x = [1, 1]
    sol = newton_krylov(f, x)
    print(sol)
    t1 = time()
    times = t1 - t0
    print(times)
Exemplo n.º 20
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def rhoBar(D, rhoL=0.4, rhoR=0.6, x=None, sigma=None, E=0, verbose=False):
    """
    Calculate the steady state profile for a 1D system.
    D, sigma - Diffusion and mobility coefficients (must supply functions even if they are constant)
    rhoL, rhoR - boundary conditions.
    E - bulk field
    """
    if x is None:
        x = np.linspace(0, 1)
    rho0 = rhoL * (1 - x) + rhoR * x + 0.02
    rho0[0] = rhoL
    rho0[-1] = rhoR
    dx = np.gradient(x)
    residual = lambda rho: steadyStateEquation(rho, rhoL, rhoR, D, sigma, E, dx
                                               )
    try:
        rhoBulk = opti.newton_krylov(residual,
                                     rho0[1:-1],
                                     method="gmres",
                                     x_rtol=1e-9,
                                     verbose=verbose)
    except opti.nonlin.NoConvergence:
        try:
            rhoBulk = opti.newton_krylov(residual,
                                         rho0[1:-1],
                                         method="lgmres",
                                         x_rtol=1e-9,
                                         verbose=verbose)
        except opti.nonlin.NoConvergence:
            try:
                rhoBulk = opti.anderson(residual,
                                        rho0[1:-1],
                                        x_rtol=1e-9,
                                        verbose=verbose)
            except opti.nonlin.NoConvergence:
                rhoBulk = opti.newton_krylov(residual,
                                             rho0[1:-1],
                                             method="gmres",
                                             x_rtol=1e-9,
                                             iter=15000,
                                             verbose=verbose)

    rho = rhoBulk
    rho = np.insert(rho, 0, rhoL)
    rho = np.append(rho, rhoR)
    return rho
Exemplo n.º 21
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def soil_temperature(g, meteo, temp_sky_eff, soil_label_prefix='other'):
    """Computes soil temperature

    Args:
        g: a multiscale tree graph object
        meteo (DataFrame): forcing meteorological variables
        t_sky_eff (float): [°C] effective sky temperature
        soil_label_prefix(str): prefix of soil nodes

    Returns:
        (double): [°C] soil temperature

    Notes:
        Heat loss into deeper soil layers is not considered.

    """

    relative_humidity, atm_pressure, temp_air = [
        float(meteo[x]) for x in ('hs', 'Pa', 'Tac')
    ]

    temp_sky_eff = utils.celsius_to_kelvin(temp_sky_eff)

    soil_nodes = [
        g.node(vid) for vid in g.property('geometry')
        if g.node(vid).label.startswith(soil_label_prefix)
    ][0]
    temp_leaves = utils.celsius_to_kelvin(
        mean(list(g.property('Tlc').values())))

    shortwave_inc = old_div(soil_nodes.Ei, (0.48 * 4.6))  # Ei not Eabs
    temp_soil = soil_nodes.Tsoil if 'Tsoil' in soil_nodes.properties(
    ) else temp_air

    def _SoilEnergyX(temp_soil):
        shortwave_abs = (
            1 - 0.25
        ) * shortwave_inc  # 0.25 is rough estimation of albedo of a bare soil
        longwave_net = e_soil * sigma * (1. * e_sky * temp_sky_eff**4 +
                                         1. * e_leaf * temp_leaves**4 -
                                         temp_soil**4)
        latent_heat = old_div(
            -lambda_ * 0.06 * utils.vapor_pressure_deficit(
                temp_air, temp_soil, relative_humidity),
            atm_pressure)  # 0.06 is gM from Bailey 2016 AFM 218-219:146-160
        sensible_heat = -0.5 * Cp * utils.celsius_to_kelvin(
            temp_soil -
            temp_air)  # 0.5 is gH from Bailey 2016 AFM 218-219:146-160
        energy_balance = shortwave_abs + longwave_net + latent_heat + sensible_heat
        return energy_balance

    t_soil0 = utils.kelvin_to_celsius(
        optimize.newton_krylov(_SoilEnergyX,
                               utils.celsius_to_kelvin(temp_soil)))

    soil_nodes.Tsoil = t_soil0

    return t_soil0
Exemplo n.º 22
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def solves():
    t0 = time.process_time()
    sol = newton_krylov(system,ainits,verbose=True,f_tol=1.0e-20,f_rtol=1.0e-10)
    print(sol)
    print(energy(sol))
    t1 = time.process_time()
    print("Calculation time =",t1-t0,"seconds")
    print('\a')
    return sol
 def direct_kinematics(self, theta1, theta2, eq_x0=[0, 0]):
     self.theta1 = theta1
     self.theta2 = theta2
     x1 = self.o1[0] + self.l1 * cos(self.theta1)
     y1 = self.o1[1] + self.l1 * sin(self.theta1)
     self.c1 = array([x1, y1])
     x2 = self.o2[0] - self.l2 * cos(self.theta2)
     y2 = self.o2[1] + self.l2 * sin(self.theta2)
     self.c2 = array([x2, y2])
     if self.NK_iter is None:
         sol = newton_krylov(self.crossing_circles_direct, eq_x0)
     else:
         sol = newton_krylov(self.crossing_circles_direct,
                             eq_x0,
                             iter=self.NK_iter)
     self.c3[0] = sol[0]
     self.c3[1] = sol[1]
     return self.c3
Exemplo n.º 24
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def Ksolves():
    t0 = time.process_time()
    print("Calculating alphas with newton_krylov method")
    sol = newton_krylov(system, seeds, verbose=True, f_rtol=1e-10)
    # print("sol")
    print("Krylov method \n", sol)
    # print(energy(sol))
    print("Krylov calculation time =", time.process_time() - t0, "seconds")
    print("\a")
    return sol
Exemplo n.º 25
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    def solve(self, maxiter=2000, toler=1e-10, verbose=0, method='lgmres'):
        if self.get_unconnected_nodes():
            self.status = Status.INVALID_SYSTEM_STATE
            return

        x0 = np.array([node.p for node in self.nodes()])
        self.map_solution_to_nodes(x0)

        inner_M = IncompressibleSystem.LinearPreconditioner(
            len(self.nodes()), self)

        try:
            p = opt.newton_krylov(self.residual,
                                  x0,
                                  verbose=verbose,
                                  inner_M=inner_M,
                                  f_tol=toler,
                                  method=method,
                                  maxiter=maxiter,
                                  inner_maxiter=1,
                                  outer_k=3)
        except NoConvergence as e:  # If iterations fail, restart using zeros
            try:
                x0 = np.zeros(len(self.nodes()))
                self.map_solution_to_nodes(x0)

                p = opt.newton_krylov(self.residual,
                                      x0,
                                      verbose=verbose,
                                      inner_M=inner_M,
                                      f_tol=toler,
                                      method=method,
                                      maxiter=maxiter)
            except NoConvergence as e:
                self.status = Status.NO_CONVERGENCE
                return
        except ValueError as e:
            self.status = Status.NAN_DETECTED
            self.map_solution_to_nodes(np.zeros(len(self.nodes())))
            return

        self.status = Status.SOLVED
        self.map_solution_to_nodes(p)
Exemplo n.º 26
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 def estimate(self, x0=None):
     if x0 is None:
         nvals = self.shape[0]*self.shape[1]
         x0 = np.zeros([nvals], dtype='complex')
         for k in range(nvals):
             x0[k] = np.complex(np.random.randn()*1e-2, np.random.randn()*1e-2)
     
     soln = newton_krylov(self.objective, x0, verbose=True)
     self.final_error = self.objective_lsq(soln)
     self.U = soln.reshape(self.shape)
Exemplo n.º 27
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def spectral(f_eval,
             t,
             y0,
             S,
             f_tol=NK_FTOL,
             y_approx=None,
             do_print=False,
             verbose=False):
    """
    This function solves directly the spectral solution (Gauss collocation formulation). That is,
    this function solves

    .. math::
        y - \\Delta{t}SF(y) = y_0

    :param function f_eval: the derivative function :math:`y' = f(t,y)`.
    :param numpy.ndarray t: the time nodes over a time step :math:`\\Delta{t}`
    :param numpy.ndarray y0: the initial solutions length, size of the problem
    :param numpy.ndarray S: the spectral integration matrix :math:`S`
    :param float f_tol: the relative tolerance of the Newton-Krylov solver
    :param numpy.ndarray y_approx: the initial guess for the Newton-Krylov solver
    :param bool verbose: a flag for the built-in Newton-Krylov solver

    :return: the spectral solution
    :rtype: numpy.ndarray
    """

    # start timing
    start = time.time()

    # the number of time nodes
    n_nodes = S.shape[1]

    # copy the initial condition [n_nodes x m]
    y0_vec = np.vstack([y0 for _ in range(n_nodes)])

    # solve H(y) = y - SF(y) -y0_vec = 0
    H = lambda y: spectral_root_finder(f_eval, t, y, y0_vec, S)

    # get the solution
    if y_approx is None:
        y_approx = y0_vec

    y = newton_krylov(H, y_approx, f_rtol=f_tol, verbose=verbose)
    #y = newton_krylov(H, y_approx, f_tol=f_tol, verbose=verbose)
    #y   = root(H, y_approx, tol=f_tol, method='krylov').x
    #y   = anderson(H, y_approx)

    # end timing
    end = time.time()

    if do_print:
        print_elapsed_time(start, end)

    return y
Exemplo n.º 28
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def solver(fobj, x0, lb=None, ub=None, options={}, method="lmmcp", jac="default", verbose=False):

    in_shape = x0.shape

    ffobj = lambda x: fobj(x.reshape(in_shape)).flatten()

    if not isinstance(jac, str):
        pp = np.prod(in_shape)

        def Dffobj(t):
            tt = t.reshape(in_shape)
            dval = jac(tt)
            return dval.reshape((pp, pp))

    elif jac == "precise":
        from numdifftools import Jacobian

        Dffobj = Jacobian(ffobj)
    else:
        Dffobj = MyJacobian(ffobj)

    if method == "fsolve":
        import scipy.optimize as optimize

        factor = options.get("factor")
        factor = factor if factor else 1
        [sol, infodict, ier, msg] = optimize.fsolve(
            ffobj, x0.flatten(), fprime=Dffobj, factor=factor, full_output=True, xtol=1e-10, epsfcn=1e-9
        )
        if ier != 1:
            print msg
    elif method == "anderson":
        import scipy.optimize as optimize

        sol = optimize.anderson(ffobj, x0.flatten())
    elif method == "newton_krylov":
        import scipy.optimize as optimize

        sol = optimize.newton_krylov(ffobj, x0.flatten())
    elif method == "lmmcp":
        from dolo.numeric.extern.lmmcp import lmmcp, Big

        if lb == None:
            lb = -Big * np.ones(len(x0.flatten()))
        else:
            lb = lb.flatten()
        if ub == None:
            ub = Big * np.ones(len(x0.flatten()))
        else:
            ub = ub.flatten()

        sol = lmmcp(ffobj, Dffobj, x0.flatten(), lb, ub, verbose=verbose, options=options)

    return sol.reshape(in_shape)
def solver(F, xin, f_tol):
    """
    A function to solve F(x) = 0

    :param F: The function F(x) = 0 to be solved
    :param xin: The initialisation of x
    :param f_tol: The precision of the solution
    :return: The solution
    """
    x = newton_krylov(F, xin, f_tol=f_tol)
    return x
 def inverse_kinematics(self, c3, eq1_x0=[0, 0], eq2_x0=[0, 0]):
     self.c3 = array(c3)
     if self.NK_iter is None:
         sol1 = newton_krylov(self.crossing_circles_inverse_c1, eq1_x0)
     else:
         sol1 = newton_krylov(self.crossing_circles_inverse_c1,
                              eq1_x0,
                              iter=self.NK_iter)
     self.c1[0] = sol1[0]
     self.c1[1] = sol1[1]
     if self.NK_iter is None:
         sol2 = newton_krylov(self.crossing_circles_inverse_c2, eq2_x0)
     else:
         sol2 = newton_krylov(self.crossing_circles_inverse_c2,
                              eq2_x0,
                              iter=self.NK_iter)
     self.c2[0] = sol2[0]
     self.c2[1] = sol2[1]
     self.theta1 = arctan2(self.c1[1] - self.o1[1], self.c1[0] - self.o1[0])
     self.theta2 = arctan2(self.c2[1] - self.o2[1], self.c2[0] - self.o2[0])
     return self.theta1, self.theta2
def nSG_solve(N, xa, xe, ta, te, dt, func_u0):
    h = (xe - xa) / (N + 1)
    x = np.arange(xa + h, xe + h / 2, h)
    u0 = func_u0(x)

    print l * dt / 2.0
    t = [ta]
    while (ta < te):
        u0 = newton_krylov(lambda a: residual(a, u0, h, dt), u0)
        ta += dt
        t.append(ta)
    return u0, x, np.array(t)
def _odeint(func, ys, ts, dt, tmax, time_residual,
            target_error=None, time_adaptor=None,
            initialisation_actions=None, actions_after_timestep=None):

    if initialisation_actions is not None:
        ys, ts = initialisation_actions(func, ys, ts)

    # Main timestepping loop
    # ============================================================
    while ts[-1] < tmax:

        t_np1 = ts[-1] + dt

        # Fill in the residual for calculating dydt and the previous time
        # and y values ready for the Newton solver.
        residual = lambda y_np1: time_residual(func, ts+[t_np1], ys+[y_np1])

        # Try to solve the system, using the previous y as an initial
        # guess. If it fails reduce dt and try again.
        try:
            y_np1 = newton_krylov(residual, ys[-1], method='gmres')
        except sp.optimize.nonlin.NoConvergence:
            dt = scale_timestep(dt, None, None, None,
                                scaling_function=failed_timestep_scaling)
            sys.stderr.write("Failed to converge, reducing time step.")
            continue

        # Execute any post-step actions requested (e.g. renormalisation,
        # simplified mid-point method update).
        if actions_after_timestep is not None:
            new_t_np1, new_y_np1 = actions_after_timestep(
                ts+[t_np1], ys+[y_np1])
            # Note: we store the results in new variables so that we can
            # easily discard this step if it fails.
        else:
            new_t_np1, new_y_np1 = t_np1, y_np1

        # Calculate the next value of dt if needed
        if time_adaptor is not None:
            try:
                dt = time_adaptor(ts+[new_t_np1], ys+[new_y_np1], target_error)

            # If the scaling factor is too small then don't store this
            # timestep, instead repeat it with the new step size.
            except FailedTimestepError, exception_data:
                dt = exception_data.new_dt
                continue

        # Update results storage (don't do this earlier in case the time
        # step fails).
        ys.append(new_y_np1)
        ts.append(new_t_np1)
Exemplo n.º 33
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        def find_servo_angle(servo):
            """
                Finds a servo angle via numerical soloution of inverse kinematic equations

                :param servo: which servo to solve
                :returns: servo angle in radians
                """
            def servo_angle_inverse_kinematic_equations(alpha):
                equations = (
                    # close loop x
                    (-1 *
                     (transformed_platform_attatchment_points[servo])[0]) +
                    (self.base_attatchment_points_bcs[servo])[0] -
                    (self.servo_arm_length * np.sin(alpha) *
                     np.sin(self.servo_pitch_angle) *
                     np.cos(self.servo_angles[servo])) -
                    (self.servo_arm_length * np.cos(alpha) *
                     np.sin(self.servo_angles[servo])),

                    # close loop y
                    (-1 *
                     (transformed_platform_attatchment_points[servo])[1]) +
                    (self.base_attatchment_points_bcs[servo])[1] -
                    (self.servo_arm_length * np.sin(alpha) *
                     np.sin(self.servo_pitch_angle) *
                     np.sin(self.servo_angles[servo])) +
                    (self.servo_arm_length * np.cos(alpha) *
                     np.cos(self.servo_angles[servo])),

                    # close loop z
                    (-1 *
                     (transformed_platform_attatchment_points[servo])[2]) +
                    (self.base_attatchment_points_bcs[servo])[2] +
                    (self.servo_arm_length * np.sin(alpha) *
                     np.cos(self.servo_pitch_angle)),

                    # second arm length
                )
                constraint = self.coupler_length**2 - equations[
                    0]**2 - equations[1]**2 - equations[2]**2
                return constraint

            if (self.servo_odd_even[servo] == -1):
                init_guess = np.pi
            else:
                init_guess = 0
            alpha = newton_krylov(servo_angle_inverse_kinematic_equations,
                                  [init_guess])[0]
            #alpha = np.mod(alpha, 2 * np.pi)
            if (alpha < 0):
                alpha += 2 * np.pi
            return alpha
Exemplo n.º 34
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 def solve(self):
     x_fp = newton_krylov(self.rootOperator,
                          self.x_0,
                          maxiter=self.numberOfIterations,
                          verbose=0,
                          x_rtol=self.convergenceCriterion,
                          method='lgmres',
                          callback=self.iterationCounter)
     print "scipy Newton Krylov converged after", self.iterationStep, "steps"
     #As a side effect, we calculate other intersting physical quantities based on the found fixpoint solution
     self.derivePhysicalQuantitiesFromFixpoint(x_fp)
     #Reset iteration counter in case solve is called various times (and class is not re-instantiated)
     self.iterationStep = 0
Exemplo n.º 35
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def solve_stat2(s, phi_ext, a_in, b_in, p0, f1, fp):
    Np = np.abs(p0)**2
    omega_1 = 2*np.pi*f1
    omega_2 = 2*np.pi*(fp-f1)
    freq, k, A, chi = s.f_k_A_chi(phi_ext)
    kappas = s.coupling_rates(phi_ext)
    omega_a = 2*pi*(freq[1] 
                  - A[1] 
                  - (chi[0, 1] + chi[2, 1] + chi[3, 1])/2
                  - chi[3, 1]*Np)
    omega_b = 2*pi*(freq[2] 
                  - A[2] 
                  - (chi[0, 2] + chi[1, 2] + chi[3, 2])/2
                  - chi[3, 2]*Np)

    delta_1, delta_2 = omega_1-omega_a, omega_2 - omega_b

    chim = s.three_waves_term(phi_ext)
    vect0 = np.array([np.real(a_in), 
                        np.imag(a_in),
                        np.real(b_in),
                        np.imag(b_in)])
    a_inr = np.real(a_in)
    a_ini = np.imag(a_in)
    b_inr = np.real(b_in)
    b_ini = np.imag(b_in)
    def optimizer(vect):
        a2 = vect[0]**2 + vect[1]**2
        b2 = vect[2]**2 + vect[3]**2
        res =  np.array([-(omega_1 - omega_a - A[1]/2*a2)*vect[1]
                        - chim*p0*vect[3]
                        - kappas[1]/2*vect[0]
                        + np.sqrt(kappas[1])*a_inr,
                        +(omega_1 - omega_a - A[1]/2*a2)*vect[0]
                        - chim*p0*vect[2]
                        - kappas[1]/2*vect[1]
                        + np.sqrt(kappas[1])*a_ini,
                        -(omega_2 - omega_b - A[2]/2*b2)*vect[3]
                        - chim*p0*vect[1]
                        - kappas[2]/2*vect[2]
                        + np.sqrt(kappas[2])*b_inr,
                        +(omega_2 - omega_b - A[2]/2*b2)*vect[2]
                        - chim*p0*vect[0]
                        - kappas[2]/2*vect[3]
                        + np.sqrt(kappas[2])*b_ini])
                          
        return res
    sol = newton_krylov(optimizer, vect0/np.sqrt(kappas[1]))
#jac = jaco(p0, delta_1, delta_2, A[1], A[2], chim, kappas[1], kappas[2], a_inr, a_ini, b_inr, b_ini)).x
    a_stat = sol[0] + 1j * sol[1]
    return (-a_in + np.sqrt(kappas[1])*a_stat)/a_in
Exemplo n.º 36
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 def fit(self, **kwargs):
     """
     Attempts to find the root of the residual of the differential equation 
     for rho at all z, given the initial guess self.rho0
     
     Uses a Newton's method with the Krylov approximation for the Jacobian
     (see scipy.optimize.newton_krylov)
     
     
     Parameters
     ----------
     
     **kwargs : keyword arguments
         Additional arguments passed to the root finder
         [see scipy.optimize.newton_krylov]
         
     Returns
     -------
     
     rho : array
         Dimensionless density, saves it to self.rho
     """
     # Set up the default options
     options = {'maxiter': 150, 'verbose': False}
     for k, v in kwargs.iteritems():
         
         options[k] = v
     
     # initial guess
     rho0 = self.rho0
     
     # Find root
     try:
         
         rho = newton_krylov(self.residual, rho0, **options)
         
     except NoConvergence as err:
         # Assume it didn't converge because f_tol was too strict
         # Read exception
         print 'Didnt converge'
         rho = err.args[0]
     
     rho[rho < 0] = 0
     # Normalize rho
     if self.rescale_rho:
         
         rho = self._rescale(rho)
         
     self.rho = rho
     self._setup_results()        
Exemplo n.º 37
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    def fit(self, **kwargs):
        """
        Attempts to find the root of the residual of the differential equation 
        for rho at all z, given the initial guess self.rho0
        
        Uses a Newton's method with the Krylov approximation for the Jacobian
        (see scipy.optimize.newton_krylov)
        
        
        Parameters
        ----------
        
        **kwargs : keyword arguments
            Additional arguments passed to the root finder
            [see scipy.optimize.newton_krylov]
            
        Returns
        -------
        
        rho : array
            Dimensionless density, saves it to self.rho
        """
        # Set up the default options
        options = {'maxiter': 150, 'verbose': False}
        for k, v in kwargs.iteritems():

            options[k] = v

        # initial guess
        rho0 = self.rho0

        # Find root
        try:

            rho = newton_krylov(self.residual, rho0, **options)

        except NoConvergence as err:
            # Assume it didn't converge because f_tol was too strict
            # Read exception
            print 'Didnt converge'
            rho = err.args[0]

        rho[rho < 0] = 0
        # Normalize rho
        if self.rescale_rho:

            rho = self._rescale(rho)

        self.rho = rho
        self._setup_results()
def complex_fsolve(fun, psi0, **kwargs):
    """
    Wrapper to solve complex-valued nonlinear equations using newton_krylov.

    (Workaround for a bug in scipy < 0.11)

    """
    m, n = psi0.shape
    def real_fun(x):
        out = fun(x[:, :n] + 1j*x[:, n:])
        return np.hstack([out.real, out.imag])
    c_out = so.newton_krylov(real_fun, np.hstack([psi0.real, psi0.imag]), 
                             **kwargs)
    return c_out[:, :n] + 1j*c_out[:, n:]
Exemplo n.º 39
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def single_stat_solve(df, metric, tol, guesses):
    print("Solving Stat", metric)
    start = time.time()
    df_temp = df.copy()
    stat_to_solve = metric  # This the stat we're solving for, e.g., 3PT% or rebounds/48
    weight = weights[metric]  # This is the denominator (all the stats are rate stats), so like 3PA or minutes played.

    df_temp = format_dataframe(df_temp, metric, metric)

    if stat_to_solve == "PM_48":
        bnds = [(0.1, 1.0), (-5000, 5000), (-5000, 5000)]
    else:
        bnds = [(0.1, 1.0), (0.001, 5000), (0.001, 5000)]

    solutions = {}
    solutions_rmse = {}
    print("Trying LBFGSB")
    decay_solve_lmbda = lambda x: decay_solve(x, df_temp, df_temp[stat_to_solve], weight)
    decay_solution_LBFGSB = newton_krylov(decay_solve_lmbda, guesses, f_tol=tol, method='lgmres')
    # decay_solution_LBFGSB = minimize(decay_solve, guesses, args=(df_temp, df_temp[stat_to_solve], weight), bounds=bnds,
    #                                  method="L-BFGS-B", tol=tol)
    solutions_rmse["LBFGSB"] = decay_solution_LBFGSB.fun
    solutions["LBFGSB"] = decay_solution_LBFGSB

    winning_model = max(solutions_rmse.items(), key=operator.itemgetter(1))[0]

    print("Best model is : " + winning_model)

    decay_solution = solutions[winning_model]

    rmse = (decay_solution.fun / df_temp[weights[metric]].sum()) ** 0.5
    print("RMSE is " + to_str(rmse))

    beta = decay_solution.x[0]
    default_den = decay_solution.x[1]
    default_num = decay_solution.x[2]
    df_proj = df.copy()
    df_proj["denom_increment"] = df_temp["denom_increment"]
    df_proj["num_increment"] = df_temp["num_increment"]
    df_proj["x" + stat_to_solve] = df_proj.groupby('PLAYER_ID').apply(decay_method_rd, beta, default_den,
                                                                      default_num).reset_index(level=0, drop=True)

    regression_results = {}
    sol = [beta, default_den, default_num, decay_solution.fun, decay_solution.success, winning_model]
    regression_results[stat_to_solve] = sol
    regression_results_temp = pd.DataFrame.from_dict(regression_results, orient='index',
                                                     columns=['beta', 'regressWeight', 'regressValue', 'square_error',
                                                              'success', 'model'])

    return regression_results_temp, df_proj["x" + stat_to_solve]
Exemplo n.º 40
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    def solve_const_vert_Force(self):
        from scipy.optimize import newton_krylov
        # constants:
        c0 = 0.010  # const profile drag
        c2 = 0.01  # c2 * alpha**2 + c0 = cDpr
        cDpi = 0.01  # drag cooefficient of pilot
        rho = 1.2
        mass = 90
        g = 9.81
        area = self.parametric_glider.shape.area
        cDl = self.obj.GliderInstance.lineset.get_normalized_drag() / area * 2
        print(cDl)
        alpha = self.alpha
        cL = self.cL
        cDi = self.cDi

        cD_ges = (cDi + np.ones_like(alpha) * (cDpi + cDl + c0) + c2 * cL**2)

        def minimize(phi):
            return np.arctan(cD_ges / cL) - self.alpha + phi

        def gz():
            return cL / cD_ges

        def vel(phi):
            return np.sqrt(2 * mass * g * np.cos(alpha - phi) / cL / rho /
                           area)

        def find_zeros(x, y):
            sign = np.sign(y[0])
            i = 1
            while i < len(y):
                if sign != np.sign(y[i]):
                    return x[i - 1] + (x[i - 1] - x[i]) * y[i - 1] / (y[i] -
                                                                      y[i - 1])
                i += 1
                if i > len(x):
                    return

        phi = newton_krylov(minimize, np.ones_like(self.alpha))
        a_p = [find_zeros(vel(phi), phi), find_zeros(gz(), phi)]
        canvas = MplCanvas()
        canvas.plot(vel(phi), gz())
        canvas.plot(a_p[0], a_p[1], marker='o')
        canvas.plot()
        canvas.axes.grid()
        canvas.draw()
        canvas.setWindowFlags(QtCore.Qt.WindowStaysOnTopHint)
        canvas.show()
Exemplo n.º 41
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def star_states_stiff(QL, QR, dt, MPL, MPR):

    PL = State(QL, MPL)
    PR = State(QR, MPR)

    x0 = zeros(42)
    x0[:21] = concatenate([QL, PL.Σ()[0], [PL.q()[0]]])
    x0[21:] = concatenate([QR, PR.Σ()[0], [PR.q()[0]]])

    def obj(x):
        return star_stepper_obj(x, QL, QR, dt, MPL, MPR)

    ret = newton_krylov(obj, x0).reshape([2, 21])

    return ret[0, :17], ret[1, :17]
	def _compute_increments(self, y, t, h, *args):
		"""Computes the increments of one RK step."""
		nu = self.rk_matrix.shape[0]
		increments = zeros((self.initial_value.size,nu)) 
		
		for i in xrange(nu):
			increment = dot(increments[:,0:i], self.rk_matrix[i,0:i]) 
			
			def func(x):
				arg1 = t + h * self.rk_nodes[i]
				arg2 = y + h * increment + h * self.rk_matrix[i,i] * x
				return self.function(arg1, arg2, *args)  - x
				
			increments[:,i] = newton_krylov(func, y, method = 'gmres')
		return increments
Exemplo n.º 43
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Arquivo: mtfa.py Projeto: dfro/mtfa
 def solve(self):
     """ solve a Poisson equation"""
     self.count = 0
     self.sol = newton_krylov(self.poisson, self.guess, 
                              method='lgmres', verbose=1,
                              x_tol=self.x_tol, maxiter=20,
                              f_tol=self.f_tol, inner_M=self.M)
     # set initial guess for next iteration in C-V
     self.guess = self.sol
     # add boundaries
     self.sol = np.insert(self.sol, 0, self.V0)
     self.sol = np.append(self.sol, 0)
     self.F = (self.sol[0]-self.sol[1])/(self.z[0]-self.z[1])
     self.nss = self.F*self.eps[0]/q0/1e4
     self.Q = self.F*self.eps[0]/1e-2
Exemplo n.º 44
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    def solve_const_vert_Force(self):
        from scipy.optimize import newton_krylov
        # constants:
        c0 = 0.010       # const profile drag
        c2 = 0.01        # c2 * alpha**2 + c0 = cDpr
        cDpi = 0.01    # drag cooefficient of pilot
        rho = 1.2
        mass = 90
        g = 9.81
        area = self.ParametricGlider.shape.area
        cDl = self.obj.GliderInstance.lineset.get_normalized_drag() / area * 2
        print(cDl)
        alpha = self.alpha
        cL = self.cL
        cDi = self.cDi

        cD_ges = (cDi + np.ones_like(alpha) * (cDpi + cDl + c0) + c2 * cL**2)

        def minimize(phi):
            return np.arctan(cD_ges / cL) - self.alpha + phi

        def gz():
            return cL / cD_ges

        def vel(phi):
            return np.sqrt(2 * mass * g * np.cos(alpha - phi) / cL / rho / area)

        def find_zeros(x, y):
            sign = np.sign(y[0])
            i = 1
            while i < len(y):
                if sign != np.sign(y[i]):
                    return x[i-1] + (x[i-1] - x[i]) * y[i-1] / (y[i] - y[i-1])
                i += 1
                if i > len(x):
                    return


        phi = newton_krylov(minimize, np.ones_like(self.alpha)) 
        a_p = [find_zeros(vel(phi), phi), find_zeros(gz(), phi)]
        canvas = MplCanvas()
        canvas.plot(vel(phi), gz())
        canvas.plot(a_p[0], a_p[1], marker="o")
        canvas.plot()
        canvas.axes.grid()
        canvas.draw()
        canvas.setWindowFlags(QtCore.Qt.WindowStaysOnTopHint)
        canvas.show()
	def _compute_increments(self, y, t, h, *args):
		"""Computes the increments of one RK step."""
		nu = self.rk_matrix.shape[0]
		n = self.initial_value.size

		def func(x):
			stacked = zeros((n * nu))
			for i in range(nu):
				pre_i = dot(x.reshape((nu, n)).T[:,0:i], self.rk_matrix[i,0:i])
				post_i = dot(x.reshape((nu, n)).T[:,i+1:nu], self.rk_matrix[i,i+1:nu])
				arg1 = t + h * self.rk_nodes[i]
				arg2 = y + h * (pre_i + post_i + self.rk_matrix[i,i] * x[n * i:n * (i + 1)])
				stacked[n * i:n * (i + 1)] = self.function(arg1, arg2, *args) - x[n * i:n * (i + 1)]
			return stacked

		return newton_krylov(func, tile(y, nu), method = 'gmres').reshape((nu, n)).T
Exemplo n.º 46
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    def get_corr_pred(self, eps, d_eps, sig, t_n, t_n1, alpha, q, kappa):
        #         g = lambda k: 0.8 - 0.8 * np.exp(-k)
        #         g = lambda k: 1. / (1 + np.exp(-2 * k + 6.))
        n_e, n_ip, n_s = eps.shape
        D = np.zeros((n_e, n_ip, 3, 3))
        D[:, :, 0, 0] = self.E_m
        D[:, :, 2, 2] = self.E_f
        sig_trial = sig[:, :, 1] / (1 - self.g(kappa)) + self.E_b * d_eps[:, :,
                                                                          1]
        xi_trial = sig_trial - q
        f_trial = abs(xi_trial) - (self.sigma_y + self.A(alpha))
        #         f_trial = abs(xi_trial) - (self.sigma_y + self.K_bar * alpha)
        elas = f_trial <= 1e-8
        plas = f_trial > 1e-8
        d_sig = np.einsum('...st,...t->...s', D, d_eps)
        sig += d_sig

        f_n1 = lambda dgamma: (f_trial - self.E_b * dgamma - self.A(
            alpha + dgamma) + self.A(alpha)) * plas

        #         try:
        d_gamma = newton_krylov(f_n1, np.zeros_like(f_trial))
        d_gamma = d_gamma * plas
        #         except:
        #             print alpha
        #             print self.sigma_y + self.A(alpha)
        #             sys.exit()
        #         Q = 0.1
        #         a = Q * self.E_b
        #         b = 2 * alpha * Q - 2 * self.E_b
        #         d_gamma = (-b + np.sqrt(b ** 2 - 4 * a * f_trial)) / 2 * a * plas
        #         d_gamma = f_trial / (self.E_b + self.K_bar + self.H_bar) * plas
        alpha += d_gamma
        kappa += d_gamma
        q += d_gamma * self.H_bar * np.sign(xi_trial)
        w = self.g(kappa)

        sig_e = sig_trial - d_gamma * self.E_b * np.sign(xi_trial)
        sig[:, :, 1] = (1 - w) * sig_e

        aAaa = derivative(self.A, alpha, dx=1e-6)
        E_p = -np.sign(xi_trial) * self.E_b / (self.E_b + aAaa) * derivative(self.g, kappa, dx=1e-6) * sig_e \
            + (1 - w) * self.E_b * aAaa / (self.E_b + aAaa)

        D[:, :, 1, 1] = (1 - w) * self.E_b * elas + E_p * plas

        return sig, D, alpha, q, kappa
Exemplo n.º 47
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def rn2rx(distpair_type: List,
          param1: List,
          param2: List,
          rnpair: float
          ) -> float:
    """
    transforms value rn in a correlation matrix to values rx

    Parameters
    ----------
    distpair_type : List
        a list containing parameter 1 and parameter 2's distribution type
    param1 : List
        a list containing statistical information about parameter 1
    param2 : List
        a list containing statistical information about parameter 2
    rnpair : float
        value containing rn from the correlation matrix

    Returns
    -------
    rx : float
        the transformed rn value


    References
    ----------
    .. [1] Razavi, S., & Gupta, H. V. (2016). A new framework for comprehensive,
           robust, and efficient global sensitivity analysis: 1. Theory. Water
           Resources Research, 52(1), 423-439. doi: 10.1002/2015WR017558
    .. [2] Razavi, S., & Gupta, H. V. (2016). A new framework for comprehensive,
           robust, and efficient global sensitivity analysis: 1. Application. Water
           Resources Research, 52(1), 423-439. doi: 10.1002/2015WR017559
    .. [3] Razavi, S., & Do, C. N. (2020). Correlation Effects? A Major but Often
           Neglected Component in Sensitivity and Uncertainty Analysis. Water Resources
           Research, 56(3). doi: /10.1029/2019WR025436
    """

    fun = lambda r: (rnpair - rx2rn(distpair_type, param1, param2, r))
    # try to find point x where fun(x) = 0
    try:
        rx = newton_krylov(F=fun, xin=rnpair, x_tol=1e-5)
    except:
        print("Function could not converge, fictive matrix was not computed")
        rx = rnpair

    return rx
Exemplo n.º 48
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def solve(reg, d, Jp):
    """Solve for the diffusion coefficient using non-linear solvers

    reg = Two region objects in a list
    d = Length between regions in cm
    Jp = Left boundary condition current

    """

    phi0m, phi0p = reg[0].flx, reg[1].flx
    phi1m, phi1p = reg[0].rJ, reg[1].rJ
    n = phi0m.shape[0]

    #@PrintRes
    def residual(D):
        """Returns how close we are to convergence in each variable

        D = Two dimensional diffusion coefficient matrix. 
            First column is left region, second is right region.

        """
        Dm, Dp = np.diag(D[:n]), np.diag(D[n:])
        logger.debug('Left region diffusion coefficient:\n%s', Dm)
        logger.debug('Right region diffusion coefficient:\n%s', Dp)
        Up = sqrtm(diag_inv(Dp).dot(reg[1].sigA))
        Um = sqrtm(diag_inv(Dm).dot(reg[0].sigA))
        Upi = np.linalg.inv(Up)
        Umi = np.linalg.inv(Um)
        logger.debug('Square root matrix error, left region:\n%s',
                     Um.dot(Um) - diag_inv(Dm).dot(reg[0].sigA))
        logger.debug('Square root matrix error, right region:\n%s',
                     Up.dot(Up) - diag_inv(Dp).dot(reg[1].sigA))
        Amm, Amp, Ap, exU, exUmm, exUmp = BCsolve(Up, Um, Dp, Dm, Jp, d)
        rm = 3.0 * Dm.dot(phi0m) - Dm.dot(d * exU.dot(Ap)) - phi1m
        rp = 3.0 * Dp.dot(phi0p) + Dp.dot(d * exU.dot(Ap)) - phi1p
        #rm = (3.0*Dm.dot( Umi.dot( exUmp.dot(Amp) - exUmm.dot(Amm) - Amp + Amm ) )
        #      - Dm.dot(d*exU.dot(Ap)) - phi1m)
        #rp = 3.0*Dp.dot( Upi.dot( exU.dot(Ap) ) ) + Dp.dot(d*exU.dot(Ap)) - phi1p
        return np.concatenate((rm, rp))

    #Initial guess is phi1 / (3.0 * phi0)
    guess = np.concatenate(
        (np.divide(phi1m, phi0m) / 3.0, np.divide(phi1p, phi0p) / 3.0))
    logger.info('starting nonlinear solver')
    sol = newton_krylov(residual, guess, method='lgmres', verbose=True)
    return sol
def get_alpha_beta(x0, y0):
    def F(P):
        Alpha = P[0]
        Beta = P[1]
        #x0 = 0.45
        #y0 = 0.35
        #X = Alpha**2 + Beta**2 - x0
        #Y = Alpha**2 - Beta**2 - y0
        #x = Alpha / (Alpha + Beta)
        #series = 1 / (1 + get_series(Alpha, Beta, x, total_it, 1))
        #print series
        # approximate so that X and Y are zeros
        #X = (x**Alpha) * ((1 - x)**Beta) / (Alpha * beta_function(Alpha, Beta)) * series - x0
        #Y = (x**(Alpha + 1)) * ((1 - x)**Beta) / ((Alpha + 1) * beta_function((Alpha + 1), Beta)) * series - y0
        #X = ((Alpha/(Alpha+Beta))**Alpha) * ((1 - (Alpha/(Alpha+Beta)))**Beta) / (Alpha * beta_function(Alpha, Beta)) * (1 / (1 + get_series(Alpha, Beta, Alpha/(Alpha+Beta), total_it, 1))) - x0
        #Y = ((Alpha/(Alpha+Beta))**(Alpha + 1)) * ((1 - (Alpha/(Alpha+Beta)))**Beta) / ((Alpha + 1) * beta_function((Alpha + 1), Beta)) * (1 / (1 + get_series(Alpha, Beta, Alpha/(Alpha+Beta), total_it, 1))) - y0
        X = beta.cdf(float(Alpha) / (Alpha + Beta), Alpha, Beta) - x0
        Y = beta.cdf(float(Alpha) / (Alpha + Beta), Alpha + 1, Beta) - y0
        return [X, Y]

    guess = [10, 5]
    max_n = 1000
    n = 1
    while n < max_n:
        try:
            sol = newton_krylov(F,
                                guess,
                                method='lgmres',
                                verbose=0,
                                rdiff=0.1,
                                maxiter=50)
            break
        except NoConvergence as e:
            guess = np.random.rand(2) * 10 + 0.1
            print(guess)
        except ValueError as e:
            guess = np.random.rand(2) * 10 + 0.1
            print(guess)
        n = n + 1
    if n == max_n:
        print(
            "Error: the chosen value is not within the computation range. Please re-choose. Suggested value: 0.3 <= x, y <= 0.5, and x >= y"
        )
        return [0, 0]
    else:
        return sol
Exemplo n.º 50
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    def do_one_step(self, t, X0):

        callback = None
        if self.diagnostics:
            callback = self.diagnostics_logger


        def optimization_function(X1):
            return X1 - X0 - self.h*vortex_rhs(self.gamma,(X0+X1)/2,self.sigma)

        X1 = newton_krylov(optimization_function, X0, 
                           f_tol=1e-14, callback=callback)
        self.diagnostics_logger.store()


        # Project down to the sphere
        for k in xrange(0, X1.shape[0]):
            X1[k, :] /= LA.norm(X1[k, :])
            
        return X1
Exemplo n.º 51
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    def eqmstate(self, rwa = False):
        """
        Approximates the equilibrium steady state of the Lindblad dynamics
        by evaluating the fixed point of the BBGKY dynamical equations. This
        is done by solving d\rho/dt = L(t)->\rho = 0 using the Newton-Krylov
        method.

        Usage:
           d = BBGKY_System_Eqm(Paramdata, MPI_COMMUNICATOR)
           eqm_state = d.eqmstate(rwa = False)

        Optional Parameters:
           rwa    =  Boolean. If set, then performs the dynamics in the rotated frame
                     i.e. the instantaneous rest frame of the drive. Default False.

        Return value:
           Numpy array. Equilibrium state represented by the quantities
           np.array([sx, sy, sz, gxx, gxy, gxz, gyx, gyy, gyz, gzx, gzy, gzz])
           where s's are blocks of spins of size N = Paramdata.latsize
           and the g's are NXN matrices of s-s connected correlations flattened in row
           major order.
        """
        self.rwa = rwa
        N = self.latsize
        #Only have root do this, then broadcast
        if self.comm.rank == root:
            a = np.zeros((3,N))
            a[2] = np.ones(N)
            c = np.zeros((3, 3, N, N))
            init_state = np.concatenate((a.flatten(), c.flatten()))
            fixed_point = newton_krylov(\
                            lambda s:lindblad_bbgky_pywrap(\
                              s, ss_final_time, self), init_state,\
                                                         verbose=self.verbose)
        else:
            fixed_point = None

        fixed_point = self.comm.bcast(fixed_point, root=root)
        return fixed_point
Exemplo n.º 52
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nx, ny = 75, 75
hx, hy = 1./(nx-1), 1./(ny-1)

P_left, P_right = 0, 0
P_top, P_bottom = 1, 0

def residual(P):
    d2x = zeros_like(P)
    d2y = zeros_like(P)

    d2x[1:-1] = (P[2:]   - 2*P[1:-1] + P[:-2]) / hx/hx
    d2x[0]    = (P[1]    - 2*P[0]    + P_left)/hx/hx
    d2x[-1]   = (P_right - 2*P[-1]   + P[-2])/hx/hx

    d2y[:,1:-1] = (P[:,2:] - 2*P[:,1:-1] + P[:,:-2])/hy/hy
    d2y[:,0]    = (P[:,1]  - 2*P[:,0]    + P_bottom)/hy/hy
    d2y[:,-1]   = (P_top   - 2*P[:,-1]   + P[:,-2])/hy/hy

    return d2x + d2y - 10*cosh(P).mean()**2

# solve
guess = zeros((nx, ny), float)
sol = newton_krylov(residual, guess, method='lgmres', verbose=1)
print('Residual: %g' % abs(residual(sol)).max())

# visualize
import matplotlib.pyplot as plt
x, y = mgrid[0:1:(nx*1j), 0:1:(ny*1j)]
plt.pcolor(x, y, sol)
plt.colorbar()
plt.show()
Exemplo n.º 53
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def StandardMap(x,y,L,k,q0,b=30.0,aa=0.0,eps=.3,m =3):

    print('b: ', b)
    #aa = -.00
    B_0 = 1.0 #in tesla
    #b = 30 #minor rad
    R_0 = 90 #major rad
    #m = 3. #external mode
    l = 10 #coil width
    a= 40
    beta = 2.0
    mu = 1.0
    beta_p = beta*(mu+1)/(beta+mu+1)
    
 
    
    hit_divert = (x>b)
    inCORE = x<b
    stopevolve = hit_divert
    
    x_new = (stopevolve == 0)*x/(1-aa*np.sin(y))
    
    # q = (q0*(x_new/a)**2) #*(1 -(1 + beta_p * (x_new/a)**2)*
    #  (1.0- (x_new/a)**2)*(a>x_new))**-1
    
    xx = x_new/a
    nu = 2.

    q = q0*(xx**2)/(1-(1-xx)**(nu+1))
   
    print('q: ', q.min(),q.max())
    y_new =  (stopevolve == 0)*(y+ 2*np.pi/q + aa*np.cos(y))
    y_new = np.mod(y_new,2*np.pi)

    #
    

    #see  "DIFFUSIVE TRANSPORT THROUGH A NONTWIST BARRIER IN TOKAMAKS"
    #eps = .3
    print(m,l,a,R_0,q0,b,eps)
    C = ((2*m*l*a**2)/(1.0*R_0*q0*b**2))*eps
    print('C: ', C/eps)
    #eps is the ration between limited and plasma currents
 
    #need to find roots of this thin2g 
    def func(x_out):
        return (-x_new + x_out +((m*b*C)/(m-1))*((x_out/b)**(m-1) )*np.sin(m*y_new))**2
    
    x_new2 = copy(x_new)

    #x_new2 =  (stopevolve == 0)* (newton_krylov(func,x_new2)) + (stopevolve)*x

    x_new2 =  (stopevolve == 0)* (newton_krylov(func,x_new2,method='bicgstab')) + (stopevolve)*x
    #print (-x_new + x_new2 +(m*b*C)/(m-1)*((x_new2/b)**(m-1) )*np.sin(m*y_new))**2
    
    y_new2 = (stopevolve == 0)*(y_new - C*(x_new2/b)**(m-2) * np.cos(m*y_new))+ (stopevolve)*y
                                
    #print 'xchange:', x_new2/x
    print(x_new2,x)
    x_new = x_new2
    y_new = np.mod(y_new2,2*np.pi)

    stay_inCORE = (x_new <b) 
    #full_orbit = (new_inSOL & inSOL) == False #can visit SOL,but can't stay
    full_orbit = (stay_inCORE & inCORE) == True 
    half_orbit = (stay_inCORE  & inCORE) == True #ok, you hit the divertor

    #print new_inSOL + inSOL
    #q = q0 + x/(2*np.pi)
    L = L + (stopevolve ==0)*((full_orbit)*q *R_0* 2*np.pi)# + \
                               #half_orbit *100* 2*q* np.pi)
    #L = L +(full_orbit)# + .5*half_orbit
 

    return x_new,y_new,L
Exemplo n.º 54
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def solve_Nics(k0):
    Nics = numpy.array([-5])
    for i in range(200):
        Nics = opt.newton_krylov(lambda N : (k0)**2 - 1e+04*fN(N),Nics)

    return Nics
Exemplo n.º 55
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 def _nksolve(sys_func, r0, precision):
     return newton_krylov(sys_func, r0, x_tol=precision)
Exemplo n.º 56
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DHp = lambda N : +1.3887943864964e-16*N*(1.0*numpy.exp(N**2/2)**1.0 - 1.0)**(-0.5)*numpy.exp(N**2/2)**1.0/(1.0e-5*(1.0*numpy.exp(N**2/2)**1.0 - 1)**1.0 + 1.0e-5)**2 - 5.55517754598561e-21*N*(1.0*numpy.exp(N**2/2)**1.0 - 1.0)**0.5*numpy.exp(N**2/2)**1.0/(1.0e-5*(1.0*numpy.exp(N**2/2)**1.0 - 1)**1.0 + 1.0e-5)**3

n = lambda N : Heavi(N)*np(N) + Heavi(-N)*nm(N)
DH = lambda N : Heavi(N)*DHp(N) + Heavi(-N)*DHm(N)

f = open('evolve_hk_test_1.dat','w')

a0 = 1e-05
n0 = numpy.exp(25)
p = 1

k0 = numpy.exp(-25)

Nics = numpy.array([-4])
for i in range(200):
    Nics = opt.newton_krylov(lambda N : (k0)**2 - 1e+04*fN(N),Nics)

print 'Nics =', Nics
print 'we have Nics'

Nshss = numpy.array([5])
for i in range(200):
    Nshss = opt.newton_krylov(lambda N : (k0)**2 - 1e+06*fN(N),Nshss)

print 'Nshss =', Nshss
print 'we have Nshss'

hk0 = numpy.zeros(1,dtype=complex)
hk0.real = (((2.*k0)**(1./2))*A(Nics))**(-1.)

Dhk0 = numpy.zeros(1,dtype=complex)
Exemplo n.º 57
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def rho_z(sigma, T, r, settings):
    """ 
    rho,z = rho_z(...)
    
    Calculates rho(z) to maintain hydrostatic equilibrium in a thin disc.  
    Assumes uniform temperature in the disc, and an infinite disc where 
    rho can be treated (locally) as only a function of z.
    
    Only calculates for z>=0, since the density is assumed to be symmetric
    about z=0
    
    The initial guess for rho (a gaussian) only really seems to work for
    Mstar >> Mdisc.  Otherwise the solution can diverge violently.
    
    * NUMERICAL CALCULATION OF RHO(Z) *
    The calculation proceeds using several steps.
    1) Make an initial guess for I, the integral of rho from z to inf.  This
        is an error function
    2) Modify length scale of the initial guess to minimize the residual
        for the differential equation governing I.  Use this as the new
        initial guess.
    3) Find the root I(z) for the differential equation governing I, with
        the boundary condition that I(0) = sigma/2
    4) Set rho = -dI/dz
    5) Find the root rho(z) for the diff. eq. governing rho.
    6) In order to satisfy the BC on I, scale rho so that:
        Integral(rho) = I(0)
    7) Repeat (5) and (6) until rho is rescaled by a factor closer to unity
        than rho_tol
        
        Steps 5-7 are done because the solution for I does not seem to
        satisfy the diff. eq. for rho very well.  But doing it this way 
        allows rho to satisfy the surface density profile
    
    * Arguments *
    
    sigma - The surface density at r
    __stdout__
    T - the temperature at r
    
    r - The radius at which rho is being calculated.  Should have units
    
    settings - ICobj settings (ie, ICobj.settings)
        
    * Output *
    Returns a 1D SimArray (see pynbody) of rho(z) and a 1D SimArray of z,
    with the same units as ICobj.settings.rho_calc.zmax
    
    """
    # Parse settings
    rho_tol = settings.rho_calc.rho_tol
    nz = settings.rho_calc.nz
    zmax = settings.rho_calc.zmax
    
    m = settings.physical.m
    M = settings.physical.M
    
    # Physical constants
    kB = SimArray(1.0,'k')
    G = SimArray(1.0,'G')
    
    # Set up default units
    mass_unit = M.units
    length_unit = zmax.units
    r = (r.in_units(length_unit)).copy()
    
    # Initial conditions/physical parameters
    rho_int = 0.5*sigma.in_units(mass_unit/length_unit**2)   # Integral of rho from 0 to inf
    a = (G*M*m/(kB*T)).in_units(length_unit)
    b = (2*np.pi*G*m/(kB*T)).in_units(length_unit/mass_unit)
    z0guess = np.sqrt(2*r*r*r/a).in_units(length_unit)# Est. scale height of disk
    z0_dummy = (2/(b*sigma)).in_units(length_unit)

    z = np.linspace(0.0,zmax,nz)
    dz = z[[1]]-z[[0]]
    
    # Echo parameters used
    print '***********************************************'
    print '* Calculating rho(z)'
    print '***********************************************'
    print 'sigma          = {0} {1}'.format(sigma,sigma.units)
    print 'zmax           = {0} {1}'.format(zmax,zmax.units)
    print 'r              = {0} {1}'.format(r,r.units)
    print 'molecular mass = {0} {1}'.format(m,m.units)
    print 'Star mass      = {0} {1}'.format(M,M.units)
    print 'Temperature    = {0} {1}'.format(T,T.units)
    print ''
    print 'rho_tol        = {0}'.format(rho_tol)
    print 'nz             = {0}'.format(nz)
    print '***********************************************'
    print 'a              = {0} {1}'.format(a,a.units)
    print 'b              = {0} {1}'.format(b,b.units)
    print 'z0guess        = {0} {1}'.format(z0guess,z0guess.units)
    print '***********************************************'
    
    print 'z0 (from sech^2) = {0} {1}'.format(z0_dummy,z0_dummy.units)
    # --------------------------------------------------------
    # STRIP THE UNITS FROM EVERYTHING!!!
    # This has to be done because many of the scipy/numpy functions used cannot
    # handle pynbody units.  Before returning z, rho, or anything else, the
    # Units must be re-introduced
    # --------------------------------------------------------
    
    rho_int, a, b, z0guess, z0_dummy, z, dz, r, T, sigma \
    = isaac.strip_units([rho_int, a, b, z0guess, z0_dummy, z, dz, r, T, sigma])
    
    # --------------------------------------------------------
    # Check sigma and T
    # --------------------------------------------------------
    if sigma < 1e-100:
        
        warn('Sigma too small.  setting rho = 0')
        rho0 = np.zeros(len(z))
        # Set up units
        rho0 = isaac.set_units(rho0, mass_unit/length_unit**3)
        z = isaac.set_units(z, length_unit)
        
        return rho0, z
        
    if T > 1e100:
        
        warn('Temperature too large.  Setting rho = 0')
        rho0 = np.zeros(len(z))
        # Set up units
        rho0 = isaac.set_units(rho0, mass_unit/length_unit**3)
        z = isaac.set_units(z, length_unit)
        
        return rho0, z  
        
    # -------------------------------------------------------------------
    # FUNCTION DEFINITIONS
    # -------------------------------------------------------------------
    def dI_dz(I_in):
        """
        Finite difference approximation of dI/dz, assuming I is odd around I(0)
        """
        I = I_in.copy()
        dI = np.zeros(len(I))
        # Fourth order center differencing
        dI[0] = (-I[2] + 8*I[1] - 7*I[0])/(6*dz)
        dI[1] = (-I[3] + 8*I[2] - 6*I[0] - I[1])/(12*dz)
        dI[2:-2] = (-I[4:] + 8*I[3:-1] -8*I[1:-3] + I[0:-4])/(12*dz)
        # Second order backward differencing for right edge
        dI[-2:] = (3*I[-2:] -4*I[-3:-1] + I[-4:-2])/(2*dz)
        
        return dI
        
    def d2I_dz2(I_in):
        
        # Finite difference for d2I/dz2 assuming it is 0 at the origin
        I = I_in.copy()
        d2I = np.zeros(len(I))
        # Boundary condition
        d2I[0] = 0
        # Centered 4th order finite difference
        d2I[1] = (-I[3] + 16*I[2] - 30*I[1] + 16*I[0] -(2*I[0] - I[1]))/(12*dz**2)
        d2I[2:-2] = (-I[4:] + 16*I[3:-1] - 30*I[2:-2] + 16*I[1:-3] - I[0:-4])/(12*(dz**2))
        # second order backward difference for right edge
        d2I[-2:] = (-2*I[-2:] + 5*I[-3:-1] -4*I[-4:-2] + I[-5:-3])/dz**2
        
        return d2I
        
    def Ires(I_in):
        """
        Calculate the residual for the differential equation governing I,
        the integral of rho from z to "infinity."
        """
        # DEFINE INITIAL CONDITION:
        I = I_in.copy()
        I[0] = rho_int
        #I[-1] = 0.0
        weight = 1.0

        res = d2I_dz2(I) + dI_dz(I)*(a*z/((z**2 + r**2)**(1.5)) + 2*b*(I[0] - I))
        
        return weight*res
        
    def drho_dz(rho_in):
        """
        Fourth order, centered finite difference for d(rho)/dz, assumes that
        rho is an even function.  The right-hand boundary is done using
        backward differencing
        """
        rho = rho_in.copy()
        drho = np.zeros(len(rho))
        drho[0] = 0.0   # defined by boundary condition, rho[0] = max(rho)
        drho[1] = (-rho[3] + 8*rho[2] - 8*rho[0] + rho[1])/(12*dz)
        drho[2:-2] = (-rho[4:] + 8*rho[3:-1] - 8*rho[1:-3] + rho[0:-4])/(12*dz)
        drho[-2:] = (3*rho[-2:] - 4*rho[-3:-1] + rho[-4:-2])/(2*dz)
        
        return drho
        
    def residual(rho_in):
        """
        Estimate d(rho)/dz
        """
        rho = rho_in.copy()
        # Estimate integral of rho
        I = np.zeros(len(rho))
        I[1:] = nInt.cumtrapz(rho,z)
        # Estimate residual 
        res = drho_dz(rho) + a*rho*z/((z**2 + r**2)**(1.5)) + 2*b*rho*I
        
        return res
        
    def erf_res(scale_size):
        
        testfct = rho_int*(1 - scipy.special.erf(z/scale_size))
        
        return abs(Ires(testfct)).sum()
        

    pass
    # -------------------------------------------------------------------
    # FIND RHO
    # -------------------------------------------------------------------
    
    maxiter = 40
    
    # Estimate the scale length of the error function
    z0 = opt.fminbound(erf_res,z0guess/100.0,5.0*z0guess)
    print 'Length scale guess: {0} {1}'.format(z0guess, length_unit)
    print 'Final length scale: {0} {1}'.format(z0, length_unit)
    
    # Begin by finding I, the integral of rho (from z to inf)
    # Assuming rho is gaussian, I is an error function
    guess = rho_int*(1 - scipy.special.erf(z/z0))
    
    # Find the root of the differential equation for I
    f_tol = rho_int * 6e-6
    try:
        
        Isol = opt.newton_krylov(Ires,guess,maxiter=maxiter,f_tol=f_tol)
        
    except NoConvergence:
        # Assume it didn't converge because f_tol was too strict
        # Read exception
        xepshun = sys.exc_info()
        # Extract rho from the exception
        Isol = xepshun[1][0]
        
    # rho is the negative derivative
    rho0 = -dI_dz(Isol)
    
    # Now apply the diff eq on rho
    for n in range(maxiter):
        
        print 'Iteration {0}'.format(n+1)
        f_tol = rho0.max() * 6e-6
        try:
            
            rho0 = opt.newton_krylov(residual,rho0,maxiter=maxiter, f_tol=f_tol)
            
        except:
            # Assume it didn't converge because f_tol was too strict
            # Read exception
            xepshun = sys.exc_info()
            # Extract rho from the exception
            rho0 = xepshun[1][0]
            
        rho_scale = rho_int/nInt.cumtrapz(rho0,z)[-1]
        print 'Scaling rho by {0}'.format(rho_scale)
        rho0 = rho0*rho_scale
        
        if abs(1-rho_scale) < rho_tol - 1:
            
            break
        
    if n >= maxiter:
        
        print 'Warning: solution to rho did not converge for r = {0}'.format(r)
    
    # Re-introduce units
    rho0 = isaac.set_units(rho0, mass_unit/length_unit**3)
    z = isaac.set_units(z, length_unit)
    
    return SimArray(rho0,'Msol au**-3'), SimArray(z,'au')
Exemplo n.º 58
0
Arquivo: jet.py Projeto: chiefenne/JET
    def solver(self):

        def residual(self, variables):
            """Summary

            Args:
                variables (TYPE): Description

            Returns:
                TYPE: Description
            """
            # All 5 unknowns
            (f, u, v, g, p, b, e) = variables
            deta = self.deta
            gsi = self.gsi
            nx = self.nx
            alpha = 3.0 / 2.0 * (gsi[nx] + gsi[nx-1]) / (gsi[nx] - gsi[nx-1])

            if self.turbulent:
                self.turbulence()

            # array slicing for indices j and n
            # index j   means [1:, ]  in first array column
            # index j-1 means [:-1, ] in first array column
            # index n   means [, 1] in second array column
            # index n-1 means [, 0] in second array column

            # boundary conditions at jet center (symmetry)
            f[0, :] = 0.0
            v[0, :] = 0.0
            p[0, :] = 0.0

            # boundary conditions at jet outer boundary (ambient)
            u[-1, :] = 0.0
            g[-1, :] = 0.0

            # ODE: f' = u
            eq1 = 1.0/deta*(f[1:, 1] - f[:-1, 1]) - 0.5*(u[2:, 1] + u[1:-1, 1])

            # ODE: u' = v
            eq2 = 1.0/deta*(u[1:, 1] - u[:-1, 1]) - 0.5*(v[2:, 1] + v[1:-1, 1])

            # ODE: g' = p
            eq3 = 1.0/deta*(g[1:, 1] - g[:-1, 1]) - 0.5*(p[2:, 1] + p[1:-1, 1])

            # PDE: Momentum
            eq4 = 1.0/deta * (b[1:, 1]*v[1:, 1] - b[:-1, 1]*v[:-1, 1]) + \
                (1.0-alpha)*0.5*(u[1:, 1]**2 - u[:-1, 1]**2) + \
                (1.0+alpha)*0.5*(f[1:, 1]*v[1:, 1] - f[:-1, 1]*v[:-1, 1]) + \
                alpha*0.25*((v[1:, 0]+v[:-1, 0])*(f[1:, 1]+f[:-1, 1]) -
                            (f[1:, 0]+f[:-1, 0])*(v[1:, 1]+v[:-1, 1])) + \
                1.0/deta * (b[1:, 0]*v[1:, 0] - b[:-1, 0]*v[:-1, 0]) + \
                (1.0+alpha)*0.5*(u[1:, 0]**2 - u[:-1, 0]**2) + \
                (1.0-alpha)*0.5*(f[1:, 0]*v[1:, 0] - f[:-1, 0]*v[:-1, 0])

            # PDE: Energy
            eq5 = 1.0/deta * (e[1:, 1]*p[1:, 1] - e[:-1, 1]*p[:-1, 1]) + \
                (1.0+alpha)*0.5*(f[1:, 1]*p[1:, 1] - f[:-1, 1]*p[:-1, 1]) - \
                alpha*(0.5*(u[1:, 1]*g[1:, 1] + u[:-1, 1]*g[:-1, 1]) +
                       0.25*((u[1:, 0]+u[:-1, 0])*(g[1:, 1]+g[:-1, 1]) -
                       (g[1:, 0]+g[:-1, 0])*(u[1:, 1]+u[:-1, 1]) +
                       (p[1:, 1]+p[:-1, 1])*(f[1:, 0]+f[:-1, 0]) -
                       (p[1:, 0]+p[:-1, 0])*(f[1:, 1]+f[:-1, 1]))) + \
                1.0/deta * (e[1:, 0]*p[1:, 0] - e[:-1, 0]*p[:-1, 0]) + \
                (1.0-alpha)*0.5*(f[1:, 0]*p[1:, 0] - f[:-1, 0]*p[:-1, 0]) + \
                alpha*0.5*(u[1:, 0]*u[1:, 0] - g[:-1, 0]*g[:-1, 0])

            return [eq1, eq2, eq3, eq4, eq5]

        def log_iterations(x, f):
            """This function is called on every iteration as callback(x, f)
            where x is the current solution and f the corresponding residual.

            Args:
                x (TYPE): Description
                f (TYPE): Description

            Returns:
                TYPE: Description
            """
            # current solution
            print x
            # current residual
            print f

        # run solver
        solution = opt.newton_krylov(residual, guess,
                                     method='lgmres',
                                     verbose=1,
                                     callback=log_iterations)

        return solution
Exemplo n.º 59
0
    (phi_wsa_v,theta_wsa_v,phi,theta,br1,v_wsa,n_wsa,T_wsa)=wsa.read('/Users/merkivg1/work/LFM-helio_2.0/WSA/fits/2010_2008_WSA_ADAPT/vel_201001032300R001_ans.fits',False)

    omega=2*pi/27.27
    phi_prime=phi-omega*1.
    ind0=where(phi_prime>0)[0][0]
    phi_prime=roll(phi_prime,-ind0)
    phi_prime[phi_prime<0]+=2*pi

    import scipy
    from scipy.interpolate import interpolate
    br1_rolled=roll(br1,-ind0,axis=1)
    fbi      = scipy.interpolate.RectBivariateSpline(theta,phi,br1_rolled,kx=1,ky=1)
    br1_new=fbi(theta,phi_prime)

    import poisson
    pois = poisson.poisson(theta,phi)
    pois.setRHS(br1_new - br0)

    guess=zeros_like(br1_new)
    sol = newton_krylov(pois.residual,guess, method='lgmres', verbose=1,f_rtol=1.e-6) #iter=100
    print('Residual: %g' % abs(pois.residual(sol)).max())

    figure();pcolormesh(sol);colorbar();title('Solution')

    # check curl
    Etheta = -1/sin(theta[:,None])*diff(sol,axis=1)
    Ephi = diff(sol,axis=0)
    figure();pcolormesh(Etheta);colorbar();title('Etheta')
    figure();pcolormesh(Ephi);colorbar();title('Ephi')

Exemplo n.º 60
0
def MF_curves_temp(R_gen, n, b_or_lg_b_min, lg_b_max=None, steps=None, selected=None,
                   nasymp=None, debug=False, usederiv=False, maxsteps=40, M_sw_solvers=500):
    ''' Numerically solves the MF equations of the many body
        master equation generated by the rate matrix R

        R - rate matrix
        lg_n_min - logarithm of minimum filling
        lg_n_max - logarithm of maximum filling
    ''' 
    
    if not lg_b_max==None and not steps==None:
        beta = np.logspace(b_or_lg_b_min, lg_b_max, steps, endpoint=True)  # filling factors
    else:
        beta = b_or_lg_b_min
    
    R = R_gen(beta[0])
    M = np.shape(R)[0]

    curves = np.zeros((len(beta), M))           # matrix for numerical results

    
    if debug:
        print "Beginne Suchalgorithmus..."
    
    for i in xrange(len(beta)):
        if debug:
            print "M =", M, ",", i *100 /float(len(beta)), "%" 
        
        red_state = 0
        
        if i == 0:
            init = np.delete(np.ones(M) * n, red_state)
        else:
            if usederiv and i>1:
                deriv = (curves[i-1] - curves[i-2]) / (beta[i-1]-beta[i-2])
                n_t = curves[i-1] + deriv * (beta[i]-beta[i-1])
                #n_t *= n / np.sum(n_t)
                init = np.delete(n_t, red_state)
            else:
                init = beta[i-1] / beta[i] * init
            
            R = R_gen(beta[i])
            print np.sum(R == 0)
        
        A = R - np.transpose(R)
        Rsum = R.sum(axis=0)
        
        if M < M_sw_solvers:
            init, info, ier, msg = fsolve(MF_equations_withA, init, args=(R, A, Rsum, M * n, red_state), fprime=MF_jac_withA, full_output=True)
        else:
            args=(R, M * n, red_state)
            func = lambda x: MF_equations(x, *args)
            try:
                init = newton_krylov(func, init, verbose=1, maxiter=500)
                ier = 1
            except:
                ier = 0

        n_t = n_bar(init, M * n, red_state)

        if (np.any(n_t < 0.) or ier != 1) and not i==0: 
            print "Fehler: Erhoehe Schrittweite"
            steps = 4
            mysuc = False
            bet_old = beta[i-1]
            oldinit = np.delete(curves[i-1], red_state)
            deriv = None
            while not mysuc:
                init = oldinit
                for bet_inter in np.logspace(np.log10(bet_old), np.log10(beta[i]), steps)[1:]:
                    if steps > maxsteps:
                        print "Erneuter Fehler, gebe auf..."
                        n_t = np.zeros(M)
                        mysuc = True
                        break
                    R = R_gen(bet_inter)
                    if usederiv and deriv != None:
                        init = init + deriv * (bet_inter-bet_old)
                    else:
                        init = bet_old / bet_inter * init
                    if M < M_sw_solvers:
                        init, info, ier, msg = fsolve(MF_equations, init, args=(R, M * n, red_state), fprime=MF_jac, full_output=True)
                        mysuc = True
                    else:
                        args=(R, M * n, red_state)
                        func = lambda x: MF_equations(x, *args)
                        try:
                            init = newton_krylov(func, init, verbose=1, maxiter=200)
                            ier = 1
                            mysuc = True
                        except:
                            ier = 0
                    
                    n_t = n_bar(init, M * n, red_state)
                    if np.any(n_t < 0.) or ier != 1: 
                        print "Erneuter Fehler, erhoehe weiter Schrittweite..."
                        steps += 4
                        mysuc = False
                        break
                    if usederiv:
                        deriv = (init - oldinit) / (bet_inter-bet_old)

                    oldinit = init
                    bet_old = bet_inter
                    
                    
            

        if np.all(n_t >= 0.):
            curves[i] = n_t
        
    return beta, curves