:orphan:
# MatNullSpaceGetVecs
get the vectors defining the null space 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatNullSpaceGetVecs(MatNullSpace sp, PetscBool *has_const, PetscInt *n, const Vec **vecs)
```
Not Collective


## Input Parameter

- ***sp -*** null space object



## Output Parameters

- ***has_cnst -*** `PETSC_TRUE` if the null space contains the constant vector, otherwise `PETSC_FALSE`
- ***n -*** number of vectors (excluding constant vector) in the null space
- ***vecs -*** orthonormal vectors that span the null space (excluding the constant vector), `NULL` if `n` is 0





## Note
These vectors and the array are owned by the `MatNullSpace` and should not be destroyed or freeded by the caller


## See Also
 [](ch_matrices), `Mat`, `MatNullSpace`, `MatNullSpaceCreate()`, `MatGetNullSpace()`, `MatGetNearNullSpace()`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/interface/matnull.c.html#MatNullSpaceGetVecs">src/mat/interface/matnull.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex49.c.html">src/ksp/ksp/tutorials/ex49.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex69.c.html">src/snes/tutorials/ex69.c</A><BR>


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