# MatPartitioningChacoSetEigenNumber
Sets the number of eigenvectors to compute by Chaco during partioning during partitioning. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatPartitioningChacoSetEigenNumber(MatPartitioning part, PetscInt num)
```
Collective


## Input Parameters

- ***part -*** the partitioning context
- ***num  -*** the number of eigenvectors



## Options Database Key

- ***-mat_partitioning_chaco_eigen_number <n> -*** Number of eigenvectors



## Note
Accepted values are 1, 2 or 3, indicating partitioning by bisection,
quadrisection, or octosection.




## See Also
 `MatPartitioningType`, `MatPartitioning`, `MATPARTITIONINGCHACO`, `MatPartitioningChacoSetEigenSolver()`, `MatPartitioningChacoGetEigenTol()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/partition/impls/chaco/chaco.c.html#MatPartitioningChacoSetEigenNumber">src/mat/partition/impls/chaco/chaco.c</A>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/partition/impls/chaco/chaco.c.html#MatPartitioningChacoSetEigenNumber_Chaco">MatPartitioningChacoSetEigenNumber_Chaco in src/mat/partition/impls/chaco/chaco.c</A><BR>


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


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