# PetscDSHasJacobian
Checks that the Jacobian functions have been set 
## Synopsis
```
#include "petscds.h" 
PetscErrorCode PetscDSHasJacobian(PetscDS ds, PetscBool *hasJac)
```
Not collective


## Input Parameter

- ***prob -*** The `PetscDS`



## Output Parameter

- ***hasJac -*** flag that pointwise function for the Jacobian has been set





## See Also
 `PetscDS`, `PetscDSGetJacobianPreconditioner()`, `PetscDSSetJacobianPreconditioner()`, `PetscDSGetJacobian()`

## Level
intermediate

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/src/dm/dt/interface/dtds.c.html#PetscDSHasJacobian">src/dm/dt/interface/dtds.c</A>


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