petsc-3.7.5 2017-01-01

MatSchurComplementGetSubMatrices

Get the individual submatrices in the Schur complement

#include "petscksp.h" 
PetscErrorCode  MatSchurComplementGetSubMatrices(Mat S,Mat *A00,Mat *Ap00,Mat *A01,Mat *A10,Mat *A11)

Collective on Mat

S -matrix obtained with MatCreateSchurComplement() (or equivalent) and implementing the action of A11 - A10 ksp(A00,Ap00) A01

	A00,A01,A10,A11	- the four parts of the original matrix A = [A00 A01; A10 A11] (A11 is optional)
	Ap00	- preconditioning matrix for use in ksp(A00,Ap00) to approximate the action of A^{-1}.

Note: A11 is optional, and thus can be NULL. The submatrices are not increfed before they are returned and should not be modified or destroyed.