# PCGAMGSetEigenvalues
Set WHAT eigenvalues WHY? 
## Synopsis
```
#include "petscpc.h" 
#include "petscksp.h" 
PetscErrorCode PCGAMGSetEigenvalues(PC pc, PetscReal emax, PetscReal emin)
```
Collective on pc


## Input Parameters

- ***pc -*** the preconditioner context
- ***emax -*** max eigenvalue


- ***emin -*** min eigenvalue



## Options Database Key

- ***-pc_gamg_eigenvalues <emin,emax> -*** estimates of the eigenvalues





## See Also
 `PCGAMG`, `PCGAMGSetUseSAEstEig()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gamg/gamg.c.html#PCGAMGSetEigenvalues">src/ksp/pc/impls/gamg/gamg.c</A>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ksp/pc/impls/gamg/gamg.c.html#PCGAMGSetEigenvalues_GAMG">PCGAMGSetEigenvalues_GAMG in src/ksp/pc/impls/gamg/gamg.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/ksp/pc/impls/gamg/gamg.c)


[Index of all PC routines](index.md)  
[Table of Contents for all manual pages](/docs/manualpages/index.md)  
[Index of all manual pages](/docs/manualpages/singleindex.md)  
