invM = mfem.DSmoother(M)
invS = mfem.GSSmoother(S)
invM.iterative_mode = False
invS.iterative_mode = False
darcyPrec = mfem.BlockDiagonalPreconditioner(block_offsets)
darcyPrec.SetDiagonalBlock(0, invM)
darcyPrec.SetDiagonalBlock(1, invS)
maxIter = 500
rtol = 1e-6
atol = 1e-10
stime = clock()
solver = mfem.MINRESSolver()
solver.SetAbsTol(atol)
solver.SetRelTol(rtol)
solver.SetMaxIter(maxIter)
solver.SetOperator(darcyOp)
solver.SetPreconditioner(darcyPrec)
solver.SetPrintLevel(1)
x.Assign(0.0)
solver.Mult(rhs, x)
solve_time = clock() - stime
if solver.GetConverged():
print("MINRES converged in " + str(solver.GetNumIterations()) +
" iterations with a residual norm of " + str(solver.GetFinalNorm()))
else:
def __init__(self, fespace, ess_bdr, visc, mu, K):
mfem.PyTimeDependentOperator.__init__(self, 2 * fespace.GetVSize(),
0.0)
rel_tol = 1e-8
skip_zero_entries = 0
ref_density = 1.0
self.z = mfem.Vector(self.Height() / 2)
self.fespace = fespace
self.viscosity = visc
M = mfem.BilinearForm(fespace)
S = mfem.BilinearForm(fespace)
H = mfem.NonlinearForm(fespace)
self.M = M
self.H = H
self.S = S
rho = mfem.ConstantCoefficient(ref_density)
M.AddDomainIntegrator(mfem.VectorMassIntegrator(rho))
M.Assemble(skip_zero_entries)
M.EliminateEssentialBC(ess_bdr)
M.Finalize(skip_zero_entries)
M_solver = mfem.CGSolver()
M_prec = mfem.DSmoother()
M_solver.iterative_mode = False
M_solver.SetRelTol(rel_tol)
M_solver.SetAbsTol(0.0)
M_solver.SetMaxIter(30)
M_solver.SetPrintLevel(0)
M_solver.SetPreconditioner(M_prec)
M_solver.SetOperator(M.SpMat())
self.M_solver = M_solver
self.M_prec = M_prec
model = mfem.NeoHookeanModel(mu, K)
H.AddDomainIntegrator(mfem.HyperelasticNLFIntegrator(model))
H.SetEssentialBC(ess_bdr)
self.model = model
visc_coeff = mfem.ConstantCoefficient(visc)
S.AddDomainIntegrator(mfem.VectorDiffusionIntegrator(visc_coeff))
S.Assemble(skip_zero_entries)
S.EliminateEssentialBC(ess_bdr)
S.Finalize(skip_zero_entries)
self.backward_euler_oper = BackwardEulerOperator(M, S, H)
J_prec = mfem.DSmoother(1)
J_minres = mfem.MINRESSolver()
J_minres.SetRelTol(rel_tol)
J_minres.SetAbsTol(0.0)
J_minres.SetMaxIter(300)
J_minres.SetPrintLevel(-1)
J_minres.SetPreconditioner(J_prec)
self.J_solver = J_minres
self.J_prec = J_prec
newton_solver = mfem.NewtonSolver()
newton_solver.iterative_mode = False
newton_solver.SetSolver(self.J_solver)
newton_solver.SetOperator(self.backward_euler_oper)
newton_solver.SetPrintLevel(1)
#print Newton iterations
newton_solver.SetRelTol(rel_tol)
newton_solver.SetAbsTol(0.0)
newton_solver.SetMaxIter(10)
self.newton_solver = newton_solver