:orphan:
# MatIncreaseOverlapSplit
Given a set of submatrices indicated by index sets across a sub communicator, replaces the index sets by larger ones that represent submatrices with additional overlap. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatIncreaseOverlapSplit(Mat mat, PetscInt n, IS is[], PetscInt ov)
```
Collective


## Input Parameters

- ***mat -*** the matrix
- ***n   -*** the number of index sets
- ***is  -*** the array of index sets (these index sets will changed during the call)
- ***ov  -*** the additional overlap requested



## `   Options Database Key

- ***-mat_increase_overlap_scalable -*** use a scalable algorithm to compute the overlap (supported by MPIAIJ matrix)





## See Also
 [](ch_matrices), `Mat`, `MatCreateSubMatrices()`, `MatIncreaseOverlap()`

## Level
developer

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


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