From: Denis Davydov Date: Tue, 14 Jun 2016 08:47:51 +0000 (+0200) Subject: parpack: update documentation and fix Exception X-Git-Tag: v8.5.0-rc1~979^2~1 X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=81a87783d3be575ba302487995b3feeb6f4e6e6b;p=dealii.git parpack: update documentation and fix Exception --- diff --git a/include/deal.II/lac/parpack_solver.h b/include/deal.II/lac/parpack_solver.h index 8ce958c12c..972de1286a 100644 --- a/include/deal.II/lac/parpack_solver.h +++ b/include/deal.II/lac/parpack_solver.h @@ -110,7 +110,21 @@ extern "C" { * of objects of type V that will contain the eigenvectors * computed. OP is an inverse operation for the matrix A - * sigma * B, where sigma is a shift value, set to zero - * by default. + * by default. Note that (P)Arpack supports other transformations, but currently + * this class implements only shift-and-invert mode. + * + * The OP can be specified either using auxiliary Shift class together + * with IterativeInverse or by using LinearOperator + * @code + * const double shift = 5.0; + * const auto op_A = linear_operator(A); + * const auto op_B = linear_operator(B); + * const auto op_shift = op_A - shift * op_B; + * SolverControl solver_control_lin (1000, 1e-10,false,false); + * + * SolverCG cg(solver_control_lin); + * const auto op_shift_invert = inverse_operator(op_shift, cg, PreconditionIdentity ()); + * @endcode * * Through the AdditionalData the user can specify some of the parameters to * be set. @@ -137,7 +151,9 @@ public: /** * An enum that lists the possible choices for which eigenvalues to compute - * in the solve() function. + * in the solve() function. Note, that this corresponds to the problem after + * shift-and-invert (the only currently supported spectral transformation) + * is applied. * * A particular choice is limited based on symmetric or non-symmetric matrix * A considered. @@ -390,7 +406,7 @@ private: * PArpackExcInfoPdnaupds. */ DeclException2 (PArpackExcConvergedEigenvectors, int, int, - << arg1 << "eigenpairs were requested, but only" + << arg1 << " eigenpairs were requested, but only " << arg2 << " converged"); DeclException2 (PArpackExcInvalidNumberofEigenvalues, int, int, @@ -876,7 +892,7 @@ void PArpackSolver::solve } Assert (iparam[4] == (int)n_eigenvalues, - PArpackExcConvergedEigenvectors(iparam[4], n_eigenvalues)); + PArpackExcConvergedEigenvectors(n_eigenvalues,iparam[4])); // both PDNAUPD and PDSAUPD compute eigenpairs of inv[A - sigma*M]*M // with respect to a semi-inner product defined by M.