:orphan:
# TSRHSJacobianTest
Compares the multiply routine provided to the `MATSHELL` with differencing on the `TS` given RHS function. 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSRHSJacobianTest(TS ts, PetscBool *flg)
```
Logically Collective


## Input Parameter

- ***TS -*** the time stepping routine



## Output Parameter

- ***flg -*** `PETSC_TRUE` if the multiply is likely correct



## Options Database Key
.   -ts_rhs_jacobian_test_mult -mat_shell_test_mult_view - run the test at each timestep of the integrator




## Note
This only works for problems defined using `TSSetRHSFunction()` and Jacobian NOT `TSSetIFunction()` and Jacobian


## See Also
 [](ch_ts), `TS`, `Mat`, `MATSHELL`, `MatCreateShell()`, `MatShellGetContext()`, `MatShellGetOperation()`, `MatShellTestMultTranspose()`, `TSRHSJacobianTestTranspose()`

## Level
advanced

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


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


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