petsc-3.7.7 2017-09-25

PCComputeExplicitOperator

Computes the explicit preconditioned operator.

Synopsis

#include "petscksp.h" 
PetscErrorCode  PCComputeExplicitOperator(PC pc,Mat *mat)

Collective on PC

Input Parameter

pc -the preconditioner object

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 when 1 processor is used and a sparse format otherwise. This routine is costly in general, and is recommended for use only with relatively small systems.

Keywords