:orphan:
# PCGAMGType
type of generalized algebraic multigrid `PCGAMG` method 
## Synopsis
```
typedef const char *PCGAMGType;
#define PCGAMGAGG       "agg"
#define PCGAMGGEO       "geo"
#define PCGAMGCLASSICAL "classical"

```

## Values

- ***`PCGAMGAGG` -*** (the default) smoothed aggregation algorithm, robust, very well tested
- ***`PCGAMGGEO` -*** geometric coarsening, uses mesh generator to produce coarser meshes, limited to triangles, not well tested
- ***`PCGAMGCLASSICAL` -*** classical algebraic multigrid preconditioner, incomplete, poorly tested





## See Also
 [](sec_pc), `PCGAMG`, `PCMG`, `PC`, `PCSetType()`, `PCGAMGSetThreshold()`, `PCGAMGSetThreshold()`, `PCGAMGSetReuseInterpolation()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscpctypes.h.html#PCGAMGType">include/petscpctypes.h</A>


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