# TSGetIJacobian
Returns the implicit Jacobian at the present timestep. 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSGetIJacobian(TS ts, Mat *Amat, Mat *Pmat, TSIJacobian *f, void **ctx)
```
Not Collective, but parallel objects are returned if ts is parallel


## Input Parameter

- ***ts  -*** The `TS` context obtained from `TSCreate()`



## Output Parameters

- ***Amat  -*** The (approximate) Jacobian of F(t,U,U_t)
- ***Pmat -*** The matrix from which the preconditioner is constructed, often the same as Amat
- ***f   -*** The function to compute the matrices
- ***ctx -*** User-defined context for Jacobian evaluation routine





## Note
You can pass in NULL for any return argument you do not need.


## See Also
 [](chapter_ts), `TS`, `TSGetTimeStep()`, `TSGetRHSJacobian()`, `TSGetMatrices()`, `TSGetTime()`, `TSGetStepNumber()`


## Level
advanced

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

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex53.c.html">src/ts/tutorials/ex53.c.html</A><BR>


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