# MatICCFactorSymbolic
Performs symbolic incomplete Cholesky factorization for a symmetric matrix.  Use `MatCholeskyFactorNumeric()` to complete the factorization. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatICCFactorSymbolic(Mat fact, Mat mat, IS perm, const MatFactorInfo *info)
```
Collective on fact


## Input Parameters

- ***fact -*** the factorized matrix obtained with `MatGetFactor()`
- ***mat -*** the matrix to be factored
- ***perm -*** row and column permutation
- ***info -*** structure containing


```none
levels - number of levels of fill.
```
```none
expected fill - as ratio of original fill.
```


## Output Parameter

- ***fact -*** the factored matrix





## Notes
Most users should employ the `KSP` interface for linear solvers
instead of working directly with matrix algebra routines such as this.
See, e.g., `KSPCreate()`.

This uses the definition of level of fill as in Y. Saad, 2003


## Developer Note
The Fortran interface is not autogenerated as the f90
interface definition cannot be generated correctly [due to `MatFactorInfo`]


## References

- **** -*** Y. Saad, Iterative methods for sparse linear systems Philadelphia: Society for Industrial and Applied Mathematics, 2003



## See Also
 `MatGetFactor()`, `MatCholeskyFactorNumeric()`, `MatCholeskyFactor()`, `MatFactorInfo`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/interface/matrix.c.html#MatICCFactorSymbolic">src/mat/interface/matrix.c</A>

## Implementations

<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/aijfact.c.html#MatICCFactorSymbolic_SeqAIJ">MatICCFactorSymbolic_SeqAIJ in src/mat/impls/aij/seq/aijfact.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/seqcusparse/aijcusparse.cu.html#MatICCFactorSymbolic_SeqAIJCUSPARSE">MatICCFactorSymbolic_SeqAIJCUSPARSE in src/mat/impls/aij/seq/seqcusparse/aijcusparse.cu</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/aij/seq/seqhipsparse/aijhipsparse.hip.c.html#MatICCFactorSymbolic_SeqAIJHIPSPARSE">MatICCFactorSymbolic_SeqAIJHIPSPARSE in src/mat/impls/aij/seq/seqhipsparse/aijhipsparse.hip.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/baij/seq/baijfact.c.html#MatICCFactorSymbolic_SeqBAIJ">MatICCFactorSymbolic_SeqBAIJ in src/mat/impls/baij/seq/baijfact.c</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/sbaij/seq/sbaijfact2.c.html#MatICCFactorSymbolic_SeqSBAIJ">MatICCFactorSymbolic_SeqSBAIJ in src/mat/impls/sbaij/seq/sbaijfact2.c</A><BR>


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