# 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;
```
```none
`PC_ASM_BASIC`        - Symmetric version where residuals from the ghost points are used
```
```none
and computed values in ghost regions are added together.
```
```none
Classical standard additive Schwarz.
```
```none
`PC_ASM_RESTRICT`     - Residuals from ghost points are used but computed values in ghost
```
```none
region are discarded.
```
```none
Default.
```
```none
`PC_ASM_INTERPOLATE`  - Residuals from ghost points are not used, computed values in ghost
```
```none
region are added back in.
```
```none
`PC_ASM_NONE`         - Residuals from ghost points are not used, computed ghost values are
```
```none
discarded.
```
```none
Not very good.
```




## See Also
 `PCASMSetType()`

## Level
beginner

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


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