# MatNullSpaceSetFunction
set a function that removes a null space from a vector out of null spaces. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatNullSpaceSetFunction(MatNullSpace sp, PetscErrorCode (*rem)(MatNullSpace, Vec, void *), void *ctx)
```
Logically Collective


## Input Parameters

- ***sp -*** the `MatNullSpace` null space object
- ***rem -*** the function that removes the null space
- ***ctx -*** context for the remove function





## See Also
 `MatNullSpace`, `MatNullSpaceDestroy()`, `MatNullSpaceRemove()`, `MatSetNullSpace()`, `MatNullSpace`, `MatNullSpaceCreate()`

## Level
advanced

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


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