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# MatAppendOptionsPrefix
Appends to the prefix used for searching for all matrix options in the database. 
## Synopsis
```
#include "petscmat.h" 
PetscErrorCode MatAppendOptionsPrefix(Mat A, const char prefix[])
```
Logically Collective


## Input Parameters

- ***A -*** the matrix
- ***prefix -*** the prefix to prepend to all option names





## Note
A hyphen (-) must NOT be given at the beginning of the prefix name.
The first character of all runtime options is AUTOMATICALLY the hyphen.


## See Also
 [](ch_matrices), `Mat`, `MatGetOptionsPrefix()`, `MatAppendOptionsPrefixFactor()`, `MatSetOptionsPrefix()`

## Level
advanced

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


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