-snes_type test

[Barry Smith]

   Check that your function evaluation is the same with 1 and 2  
processors.

   Check the ordering of the unknowns and how they are partitioned and  
that proper ghost point values are set.


On Apr 21, 2009, at 2:05 PM, (Rebecca) Xuefei YUAN wrote:

> Hi,
>
> I am testing my hand coded jacobian matrix in multi processors with  
> the option "-snes_type test -snes_test_display", and I find that
> 1) my hand coded jacobian is different from the finite difference  
> jacobian running with 2 processors.
> But
> 2) my jacobian is the same as the finite difference jacobian matrix  
> running with 1 single processor.
> Also
> 3) my hand coded jacobian with 1 processor is the same as my hand  
> coded jacobian with 2 processors.
>
> Where could be wrong about multiprocessors' jacobian matrix?
>
> Thanks very much!
> -- 
> (Rebecca) Xuefei YUAN
> Department of Applied Physics and Applied Mathematics
> Columbia University
> Tel:917-399-8032
> www.columbia.edu/~xy2102
>