# MatNestGetISs
Returns the index sets partitioning the row and column spaces of a `MATNEST` 
## Synopsis
```
#include "petscmat.h"   
PetscErrorCode MatNestGetISs(Mat A, IS rows[], IS cols[])
```
Not collective


## Input Parameter

- ***A  -*** `MATNEST` matrix



## Output Parameters

- ***rows -*** array of row index sets
- ***cols -*** array of column index sets





## Note
The user must have allocated arrays of the correct size. The reference count is not increased on the returned ISs.


## See Also
 `MATNEST`, `MatNestGetSubMat()`, `MatNestGetSubMats()`, `MatNestGetSize()`, `MatNestGetLocalISs()`, `MATNEST`,
`MatCreateNest()`, `MatNestGetSubMats()`, `MatNestSetSubMats()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/nest/matnest.c.html#MatNestGetISs">src/mat/impls/nest/matnest.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/ksp/tutorials/ex81.c.html">src/ksp/ksp/tutorials/ex81.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/tutorials/ex70.c.html">src/snes/tutorials/ex70.c.html</A><BR>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/nest/matnest.c.html#MatNestGetISs_Nest">MatNestGetISs_Nest in src/mat/impls/nest/matnest.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/impls/nest/matnest.c)


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