# TSGetComputeExactError
Get the function used to automatically compute the exact error for the timestepping. 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSGetComputeExactError(TS ts, PetscErrorCode (**exactError)(TS, Vec, Vec))
```
Not collective


## Input Parameter

- ***ts -*** time stepping context



## Output Parameter

- ***exactError -*** The function which computes the solution error



## Calling sequence for exactError
```none
PetscErrorCode exactError(TS ts, Vec u)
```

- ***ts -*** The timestepping context
- ***u  -*** The approximate solution vector
- ***e  -*** The input vector in which the error is stored





## See Also
 [](chapter_ts), `TS`, `TSGetComputeExactError()`, `TSComputeExactError()`

## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/interface/ts.c.html#TSGetComputeExactError">src/ts/interface/ts.c</A>


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[Index of all TS routines](index.md)  
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[Index of all manual pages](/docs/manualpages/singleindex.md)  
