:orphan:
# TaoGetConstraintTolerances
Gets constraint tolerance parameters used in `TaoSolve()` convergence tests 
## Synopsis
```
#include "petsctao.h" 
PetscErrorCode TaoGetConstraintTolerances(Tao tao, PetscReal *catol, PetscReal *crtol)
```
Not Collective


## Input Parameter

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



## Output Parameters

- ***catol -*** absolute constraint tolerance, constraint norm must be less than `catol` for used for gatol convergence criteria
- ***crtol -*** relative constraint tolerance, constraint norm must be less than `crtol` for used for gatol, gttol convergence criteria





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

## Level
intermediate

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