# 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 Parameters
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 only the RHS function and Jacobian NOT IFunction and IJacobian


## See Also
 [](chapter_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>


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