:orphan:
# DMSNESSetNGS
set `SNES` Gauss-Seidel relaxation function 
## Synopsis
```
#include "petscsnes.h" 
#include "petscdm.h" 
PetscErrorCode DMSNESSetNGS(DM dm, PetscErrorCode (*f)(SNES, Vec, Vec, void *), void *ctx)
```
Not Collective


## Input Parameters

- ***dm -*** `DM` to be used with `SNES`
- ***f  -*** relaxation function, see `SNESGSFunction`
- ***ctx -*** context for residual evaluation





## Note
`SNESSetNGS()` is normally used, but it calls this function internally because the user context is actually
associated with the `DM`.  This makes the interface consistent regardless of whether the user interacts with a `DM` or
not.


## Dveloper Note
If `DM` took a more central role at some later date, this could become the primary method of supplying the smoother


## See Also
 `DMSNESSetContext()`, `SNESSetFunction()`, `DMSNESSetJacobian()`, `DMSNESSetFunction()`, `SNESGSFunction`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/utils/dmsnes.c.html#DMSNESSetNGS">src/snes/utils/dmsnes.c</A>


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[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)