Hi Mani,
please check the return value of *all* function calls from PETSc, e.g.
ierr = DMCreateGlobalVector(da, &soln);CHKERRQ(ierr);
instead of just
DMCreateGlobalVector(da, &soln);
Most likely one of the routines threw an error, but your code just kept
going, producing wrong results.
Best regards,
Karli
On 01/25/2014 05:35 AM, Mani Chandra wrote:
Hi Everyone,
I'm trying to use TS with ViennaCL vecs/mats and residual evaluation on
device and have encountered some problems. I have attached a small test
code that illustrates the issue.
The code simply advects a blob diagonally using TS. I have written the
residual evaluation function using 1) the usual Petsc vectors
(VecGetArray) and 2) using ViennaCL vectors (VecViennaCLGetArrayRead/Write).
Run the code using the following:
./petsc_opencl -ts_monitor -snes_monitor -ts_max_steps 1000 -ts_type
theta -ts_dt 10 -snes_rtol 1e-4 -ts_final_time 1000
-ts_monitor_draw_solution
Case 1) No ViennaCL anywhere. I simply use the usual Petsc vectors and
set the residual evaluation function as ComputeResidual (line no. 55).
This case works and the blob is indeed advected as can be seen. (I
haven't bothered with the boundaries. The simulation just stops before
the blob hits the boundaries).
Case 2) We again use the ComputeResidual but now enable ViennaCL vecs
and mats (line nos. 48, 49). This case does NOT work. The SNES monitor
shows convergence but the solution makes no sense.
Case 3) We now use ComputeResidualViennaCL (line no. 56). This does NOT
work either with or without enabling the ViennaCL vecs (line nos. 48, 49).
Cheers,
Mani
