:orphan:
# SNESVIComputeFunction
Provides the function that reformulates a system of nonlinear equations in mixed complementarity form to a system of nonlinear equations in semismooth form. 
## Synopsis
```
#include "petscsnes.h" 
PetscErrorCode SNESVIComputeFunction(SNES snes, Vec X, Vec phi, void *functx)
```

## Input Parameters

- ***snes -*** the SNES context
- ***X -*** current iterate
- ***functx -*** user defined function context



## Output Parameter

- ***phi -*** the evaluation of Semismooth function at X





## See Also
 `SNESVINEWTONSSLS`, `SNESVIComputeMeritFunction()`

## Level
developer

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/impls/vi/ss/viss.c.html#SNESVIComputeFunction">src/snes/impls/vi/ss/viss.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/snes/impls/vi/ss/viss.c)


[Index of all SNES routines](index.md)  
[Table of Contents for all manual pages](/manualpages/index.md)  
[Index of all manual pages](/manualpages/singleindex.md)  
