[petsc-users] Jacobian of TS problem

[Barry Smith]

  Switch to petsc-3.2 it has a much improved set of ODE integraters

  The matrix generation (and its non-zero pattern) are handled in DMGetMatrix().

   To get access to the values of Jacobian at each Newton step provide your own custom monitor with SNESMonitorSet() then inside your custom monitor call SNESGetJacobian() and call MatView() on the retrieved matrix.

   Barry

On Sep 19, 2011, at 7:14 PM, yuxuan wrote:

> Hi all,
> 
> I am running the example:
> http://www.mcs.anl.gov/petsc/petsc-as/snapshots/petsc-3.1/src/ts/examples/tutorials/ex7.c
> 
> I found that there is no user-provided jacobian data structure function for Finite Difference Jacobian Approximation. And also how can I have look at the values of the Jacobian Matrix. The Matview can show the value, however how I can call it within the solving processes. 
> 
> Thanks
> 
> Xuan
>  
> 
>