# PetscIsCloseAtTol
Returns whether the two floating point numbers are close at a given relative and absolute tolerances. 
## Synopsis
```
PetscBool PetscIsCloseAtTol(PetscReal a, PetscReal b, PetscReal rtol, PetscReal atol)
```

## Input Parameters

- ***a -*** first floating point number
- ***b -*** second floating point number
- ***rtol -*** relative tolerance
- ***atol -*** absolute tolerances



## Reference

- **** -*** https://www.python.org/dev/peps/pep-0485/





## See Also
 `PetscEqualReal()`, `PetscEqualScalar()`

## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/sys/utils/mathclose.c.html#PetscIsCloseAtTol">src/sys/utils/mathclose.c</A>


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[Edit on GitLab](https://gitlab.com/petsc/petsc/-/edit/release/src/sys/utils/mathclose.c)


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