Ejemplo n.º 1
0
    def __init__(self, A, solver=default_solver, parameters={}):
        from PyTrilinos import Epetra, Amesos
        from dolfin import info
        from time import time
        self.A = A  # Keep reference
        T = time()
        self.problem = Epetra.LinearProblem()
        self.problem.SetOperator(A.down_cast().mat())
        self.solver = Amesos.Factory().Create(solver, self.problem)
        if (self.solver == None):
            raise RuntimeError('Failed to create Amesos solver: ' + solver)

        # This prevents a use-after-free crash for the MPI communicator. It
        # enforces that the solver is destroyed before A.
        self.solver.A = A

        self.solver.SetParameters(parameters)
        if self.solver is None:
            raise RuntimeError("Unknown solver '%s'" % solver)
        err = self.solver.SymbolicFactorization()
        if err != 0:
            raise RuntimeError("Amesos " + solver +
                               " symbolic factorization failed, err=%d" % err)
        err = self.solver.NumericFactorization()
        if err != 0:
            raise RuntimeError("Amesos " + solver +
                               " numeric factorization failed, err=%d" % err)
        info('constructed direct solver (using %s) in %.2f s' %
             (solver, time() - T))
Ejemplo n.º 2
0
    def __init__(self,
                 tolerance=1e-10,
                 iterations=10,
                 precon=None,
                 maxIterations=10):
        """
        :Parameters:
          - `tolerance`: The required error tolerance.
          - `iterations`: The maximum number of iterative steps to perform.

        """

        iterations = min(iterations, maxIterations)

        TrilinosSolver.__init__(self,
                                tolerance=tolerance,
                                iterations=iterations,
                                precon=None)

        if precon is not None:
            import warnings
            warnings.warn(
                "Trilinos KLU solver does not accept preconditioners.",
                UserWarning,
                stacklevel=2)
        self.Factory = Amesos.Factory()
Ejemplo n.º 3
0
 def query(which=None):
     """Return list of available solver backends, or True/False if given a solver name"""
     from PyTrilinos import Amesos
     factory = Amesos.Factory()
     if which is None:
         avail = []
         for s in serial_solvers + parallel_solvers:
             if factory.Query(s):
                 avail.append(s)
         return avail
     return factory.Query(which)
Ejemplo n.º 4
0
    def direct_solve(self, jac, rhs):
        '''Currently unused direct solver that was used for testing.'''

        A = Epetra.CrsMatrix(Epetra.Copy, self.map, 27)
        for i in range(len(jac.begA)-1):
            if i == self.dim:
                A[i, i] = -1
                continue
            for j in range(jac.begA[i], jac.begA[i+1]):
                if jac.jcoA[j] != self.dim:
                    A[i, jac.jcoA[j]] = jac.coA[j]
        A.FillComplete()

        rhs[self.dim] = 0
        x = Vector(rhs)

        problem = Epetra.LinearProblem(A, x, rhs)
        factory = Amesos.Factory()
        solver = factory.Create('Klu', problem)
        solver.SymbolicFactorization()
        solver.NumericFactorization()
        solver.Solve()

        return x
Ejemplo n.º 5
0
    def __init__(self, ckt):
        # Init base class
        _NLFunction.__init__(self)

        # Save ckt instance
        self.ckt = ckt
        # Make sure circuit is ready (analysis should take care)
        assert ckt.nD_ref

        # Allocate matrices/vectors
        # Create Epetra CrsMatrix: need communicator and map
        comm = Epetra.SerialComm()
        # Map: numelem, base index, communicator
        map = Epetra.Map(self.ckt.nD_dimension, 0, comm)
        # TODO: Find a good estimate for nnzRow
        nnzRow = min(10, self.ckt.nD_dimension)
        # G here is G1 = G + G0 in documentation
        self.G = Epetra.CrsMatrix(Epetra.Copy, map, nnzRow)
        # Jac is (G1 + di/dv) in doc
        self.Jac = Epetra.CrsMatrix(Epetra.Copy, map, nnzRow)
        # Allocate several vectors
        self.xVec = Epetra.Vector(map)
        self.iVec = Epetra.Vector(map)
        self.sVec = Epetra.Vector(map)
        self.errVec = Epetra.Vector(map)
        self.deltaxVec = Epetra.Vector(map)

        if hasattr(self.ckt, 'nD_namRClist'):
            # Allocate external currents vector
            self.extSVec = np.empty(self.ckt.nD_dimension)

        # Generate G and Jac sparse matrices
        # ----------------------------------
        self._get_Gnz()
        self.Jacnz = [([], []) for i in xrange(self.ckt.nD_dimension)]

        # Insert linear contributions into G and Jac (to fix structure)
        for row, data in enumerate(self.Gnz):
            self.G.InsertGlobalValues(row, *data)
            self.Jac.InsertGlobalValues(row, *data)

        # Finalize G (which should not change any more unless parameter sweep)
        assert not self.G.FillComplete()
        assert not self.G.OptimizeStorage()

        # Add nonlinear contribution to Jac. Insert ones for now as the
        # matrix values will be discarded anyway.
        for elem in self.ckt.nD_nlinElem:
            outJac = np.ones((len(elem.csOutPorts), len(elem.controlPorts)),
                             dtype=float)
            set_Jac(self.Jacnz, elem.nD_cpos, elem.nD_cneg, elem.nD_vpos,
                    elem.nD_vneg, outJac)

        for row, data in enumerate(self.Jacnz):
            self.Jac.InsertGlobalValues(row, *data)

        # Finalize and symbolically factor Jac
        assert not self.Jac.FillComplete()
        assert not self.Jac.OptimizeStorage()

        # Create pytrilinos solver
        problem = Epetra.LinearProblem(self.Jac, self.deltaxVec, self.errVec)
        factory = Amesos.Factory()
        self.solver = factory.Create("Klu", problem)
        assert not self.solver.SymbolicFactorization()
Ejemplo n.º 6
0
    # }

    # prec = ML.MultiLevelPreconditioner(P_epetra, False)
    # prec.SetParameterList(mlList)
    # prec.ComputePreconditioner()

    # solver = AztecOO.AztecOO(A_epetra, x_epetra, b_epetra)
    # solver.SetPrecOperator(prec)
    # solver.SetAztecOption(AztecOO.AZ_solver, AztecOO.AZ_gmres);
    # solver.SetAztecOption(AztecOO.AZ_output, 100);
    # err = solver.Iterate(20000, 1e-10)

    tic()
    problem = Epetra.LinearProblem(A_epetra, x_epetra, b_epetra)
    print '\n\n\n\n\n\n'
    factory = Amesos.Factory()
    solver = factory.Create("Amesos_Umfpack", problem)
    # solver = factory.Create("MUMPS", problem)
    amesosList = {"PrintTiming": True, "PrintStatus": True}
    solver.SetParameters(amesosList)
    solver.SymbolicFactorization()
    solver.NumericFactorization()
    solver.Solve()
    soln = problem.GetLHS()
    print "||x_computed||_2 =", soln.Norm2()
    # solver.PrintTiming()
    print '\n\n\n\n\n\n'

    if case == 1:
        ue = Expression(("20*x[0]*pow(x[1],3)", "5*pow(x[0],4)-5*pow(x[1],4)"))
        pe = Expression("60*pow(x[0],2)*x[1]-20*pow(x[1],3)+5")