:orphan:
# MatMFFDRegister
Adds a method to the `MATMFFD` registry. 
## Synopsis
```
#include "petscmat.h"   
PetscErrorCode MatMFFDRegister(const char sname[], PetscErrorCode (*function)(MatMFFD))
```
Not Collective


## Input Parameters

- ***sname -*** name of a new user-defined compute-h module
- ***function -*** routine to create method context





## Note
`MatMFFDRegister()` may be called multiple times to add several user-defined solvers.


## Sample usage
```none
   MatMFFDRegister("my_h", MyHCreate);
```


Then, your solver can be chosen with the procedural interface via
```none
`MatMFFDSetType`(mfctx, "my_h")
```
or at runtime via the option
```none
-mat_mffd_type my_h
```


## See Also
 [](ch_matrices), `Mat`, `MATMFFD`, `MatMFFDRegisterAll()`, `MatMFFDRegisterDestroy()`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/mat/impls/mffd/mffd.c.html#MatMFFDRegister">src/mat/impls/mffd/mffd.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/mat/impls/mffd/mffd.c)


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