:orphan:
# SNESLineSearchBTSetAlpha
Sets the descent parameter, alpha, in the `SNESLINESEARCHBT` variant. 
## Synopsis
```
#include "petscsnes.h"  
PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch linesearch, PetscReal alpha)
```

## Input Parameters

- ***linesearch -*** linesearch context
- ***alpha -*** The descent parameter





## See Also
 `SNESLineSearch`, `SNESLineSearchSetLambda()`, `SNESLineSearchGetTolerances()`, `SNESLINESEARCHBT`, `SNESLineSearchBTGetAlpha()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/linesearch/impls/bt/linesearchbt.c.html#SNESLineSearchBTSetAlpha">src/snes/linesearch/impls/bt/linesearchbt.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/snes/linesearch/impls/bt/linesearchbt.c)


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