MatNullSpaceCreate

Creates a data structure used to project vectors out of null spaces.

#include "petscmat.h" 
int MatNullSpaceCreate(MPI_Comm comm,int has_cnst,int n,Vec *vecs,MatNullSpace *SP)

Collective on MPI_Comm

	comm	- the MPI communicator associated with the object
	has_cnst	- PETSC_TRUE if the null space contains the constant vector; otherwise PETSC_FALSE
	n	- number of vectors (excluding constant vector) in null space
	vecs	- the vectors that span the null space (excluding the constant vector); these vectors must be orthonormal. These vectors are NOT copied, so do not change them after this call. You should free the array that you pass in.

SP -the null space context

Section 4.15 Solving Singular Systems -

PC, null space, create