# PCJacobiType
What elements are used to form the Jacobi preconditioner 
## Synopsis
```
typedef enum {
  PC_JACOBI_DIAGONAL,
  PC_JACOBI_ROWMAX,
  PC_JACOBI_ROWSUM
} PCJacobiType;
```

## Values

- ***`PC_JACOBI_DIAGONAL` -*** use the diagonal entry, if it is zero use one
- ***`PC_JACOBI_ROWMAX` -*** use the maximum absolute value in the row
- ***`PC_JACOBI_ROWSUM` -*** use the sum of the values in the row (not the absolute values)





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

## Level
intermediate

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


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