# KSPGMRESCGSRefinementType
How the classical (unmodified) Gram-Schmidt is performed. 
## Synopsis
```
typedef enum {
  KSP_GMRES_CGS_REFINE_NEVER,
  KSP_GMRES_CGS_REFINE_IFNEEDED,
  KSP_GMRES_CGS_REFINE_ALWAYS
} KSPGMRESCGSRefinementType;
```



## See Also
 `KSPGMRESClassicalGramSchmidtOrthogonalization()`, `KSPGMRESSetOrthogonalization()`, `KSPGMRESGetOrthogonalization()`,
`KSPGMRESSetCGSRefinementType()`, `KSPGMRESGetCGSRefinementType()`, `KSPGMRESModifiedGramSchmidtOrthogonalization()`


## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscksp.h.html#KSPGMRESCGSRefinementType">include/petscksp.h</A>


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