# TSGetI2Jacobian
Returns the implicit Jacobian at the present timestep. 
## Synopsis
```
#include "petscts.h"  
PetscErrorCode TSGetI2Jacobian(TS ts, Mat *J, Mat *P, TSI2Jacobian *jac, void **ctx)
```
Not Collective, but parallel objects are returned if TS is parallel


## Input Parameter

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



## Output Parameters

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



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




## See Also
 `TSGetTimeStep()`, `TSGetMatrices()`, `TSGetTime()`, `TSGetStepNumber()`, `TSSetI2Jacobian()`, `TSGetI2Function()`, `TSCreate()`


## Level
advanced

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/interface/ts.c.html#TSGetI2Jacobian">src/ts/interface/ts.c</A>

## Examples
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/ts/tutorials/ex44.c.html">src/ts/tutorials/ex44.c.html</A><BR>


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