petsc-3.13.6 2020-09-29
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KSPComputeOperator

Computes the explicit preconditioned operator, including diagonal scaling and null space removal if applicable.

Synopsis

#include "petscksp.h" 
PetscErrorCode  KSPComputeOperator(KSP ksp, MatType mattype, Mat *mat)
Collective on ksp

Input Parameter

ksp - the Krylov subspace context
mattype - the matrix type to be used

Output Parameter

mat -the explict preconditioned operator

Notes

This computation is done by applying the operators to columns of the identity matrix.

Currently, this routine uses a dense matrix format for the output operator if mattype == NULL. This routine is costly in general, and is recommended for use only with relatively small systems.

See Also

KSPComputeEigenvaluesExplicitly(), PCComputeOperator(), KSPSetDiagonalScale(), KSPSetNullSpace(), MatType

Level

advanced

Location

src/ksp/ksp/interface/eige.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages