# PCASMType
Type of additive Schwarz method to use 
## Synopsis
```
typedef enum {
  PC_ASM_BASIC       = 3,
  PC_ASM_RESTRICT    = 1,
  PC_ASM_INTERPOLATE = 2,
  PC_ASM_NONE        = 0
} PCASMType;
```

## Values

- ***`PC_ASM_BASIC`        -*** Symmetric version where residuals from the ghost points are used
and computed values in ghost regions are added together.
Classical standard additive Schwarz.
- ***`PC_ASM_RESTRICT`     -*** Residuals from ghost points are used but computed values in ghost
region are discarded.
Default.
- ***`PC_ASM_INTERPOLATE`  -*** Residuals from ghost points are not used, computed values in ghost
region are added back in.
- ***`PC_ASM_NONE`         -*** Residuals from ghost points are not used, computed ghost values are
discarded.
Not very good.





## See Also
 [](sec_pc), `PC`, `PCASM`, `PCASMSetType()`

## Level
beginner

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


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