:orphan:
# TaoGetTolerances
gets the current values of some tolerances used for the convergence testing of `TaoSolve()` 
## Synopsis
```
#include "petsctao.h" 
PetscErrorCode TaoGetTolerances(Tao tao, PetscReal *gatol, PetscReal *grtol, PetscReal *gttol)
```
Not Collective


## Input Parameter

- ***tao -*** the `Tao` context



## Output Parameters

- ***gatol -*** stop if norm of gradient is less than this
- ***grtol -*** stop if relative norm of gradient is less than this
- ***gttol -*** stop if norm of gradient is reduced by a this factor





## Note
`NULL` can be used as an argument if not all tolerances values are needed


## See Also
 [](ch_tao), `Tao`, `TaoSetTolerances()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/tao/interface/taosolver.c.html#TaoGetTolerances">src/tao/interface/taosolver.c</A>


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


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