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


#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


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.

Level: advanced

See Also

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