:orphan:
# SNESSetFunctionDomainError
tells `SNES` that the input vector, a proposed new solution, to your function you provided to `SNESSetFunction()` is not in the functions domain. For example, a step with negative pressure. 
## Synopsis
```
#include "petscsnes.h"  
PetscErrorCode SNESSetFunctionDomainError(SNES snes)
```
Logically Collective


## Input Parameter

- ***snes -*** the `SNES` context





## Notes
If this is called the `SNESSolve()` stops iterating and returns with a `SNESConvergedReason` of `SNES_DIVERGED_FUNCTION_DOMAIN`

You should always call `SNESGetConvergedReason()` after each `SNESSolve()` and verify if the iteration converged (positive result) or diverged (negative result).

You can direct `SNES` to avoid certain steps by using `SNESVISetVariableBounds()`, `SNESVISetComputeVariableBounds()` or
`SNESLineSearchSetPreCheck()`, `SNESLineSearchSetPostCheck()`


## See Also
 [](ch_snes), `SNESCreate()`, `SNESSetFunction()`, `SNESFunction`, `SNESSetJacobianDomainError()`, `SNESVISetVariableBounds()`,
`SNESVISetComputeVariableBounds()`, `SNESLineSearchSetPreCheck()`, `SNESLineSearchSetPostCheck()`, `SNESConvergedReason`, `SNESGetConvergedReason()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/interface/snes.c.html#SNESSetFunctionDomainError">src/snes/interface/snes.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex10.c.html">src/ts/tutorials/ex10.c</A><BR>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/snes/interface/snes.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)