# SNESLINESEARCHBASIC
This line search implementation is not a line search at all; it simply uses the full step.  Thus, this routine is intended for methods with well-scaled updates; i.e. Newton's method (`SNESNEWTONLS`), on well-behaved problems. Also named as `SNESLINESEARCHNONE` 
## Options Database Keys

- ***-snes_linesearch_damping <damping> -*** search vector is scaled by this amount, default is 1.0
- ***-snes_linesearch_norms <flag> -*** whether to compute norms or not, default is true (SNESLineSearchSetComputeNorms())



## Note
For methods with ill-scaled updates (`SNESNRICHARDSON`, `SNESNCG`), a small
damping parameter may yield satisfactory but slow convergence despite
the lack of the line search.




## See Also
 `SNES`, `SNESLineSearch`, `SNESLineSearchType`, `SNESLineSearchCreate()`, `SNESLineSearchSetType()`, `SNESLineSearchSetDamping()`, `SNESLineSearchSetComputeNorms()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/snes/linesearch/impls/basic/linesearchbasic.c.html#SNESLINESEARCHBASIC">src/snes/linesearch/impls/basic/linesearchbasic.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex22.c.html">src/ts/tutorials/ex22.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex22f.F90.html">src/ts/tutorials/ex22f.F90.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/utils/dmplexlandau/tutorials/ex1.c.html">src/ts/utils/dmplexlandau/tutorials/ex1.c.html</A><BR>
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/utils/dmplexlandau/tutorials/ex1f90.F90.html">src/ts/utils/dmplexlandau/tutorials/ex1f90.F90.html</A><BR>


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


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