:orphan:
# PCSide
If the preconditioner is to be applied to the left, right or symmetrically around the operator. 
## Synopsis
```
typedef enum {
  PC_SIDE_DEFAULT = -1,
  PC_LEFT,
  PC_RIGHT,
  PC_SYMMETRIC
} PCSide;
```

## Values

- ***`PC_LEFT` -*** applied after the operator is applied
- ***`PC_RIGHT` -*** applied before the operator is applied
- ***`PC_SYMMETRIC` -*** a portion of the preconditioner is applied before the operator and the transpose of this portion is applied after the operator is applied.





## Note
Certain `KSPType` support only a subset of `PCSide` values


## See Also
 [](sec_pc), `PC`, `KSPSetPCSide()`

## Level
beginner

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


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