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LLNL
onemkl linear solver doesn't have a default difference quotient jacobian?
Hello again, I finally was able to compile link and execute my model with the onemkl dense linear solver. The problem now is that at initialization time I get this error
[CVLS ERROR] cvLsInitialize
No Jacobian constructor available for SUNMatrix type
[CVODE ERROR] cvInitialSetup
The linear solver's init routine failed.
I'm using the following initialization code:
/* Create dense SUNMatrix for use in linear solves */
A = SUNMatrix_OneMklDense(y_len, y_len, SUNMEMTYPE_DEVICE, memhelper, &s->qspccQueue, s->sunctx);
if (check_flag((void *)A, "SUNMatrix_OneMklDense", 0)) return s;
s->matrix = A; /* save for deallocation */
// Create the SUNLinearSolver object for use by CVode
LS = SUNLinSol_OneMklDense(s->y, A, s->sunctx);
if (check_flag((void *)LS, "SUNLinSol_OneMklDense", 0)) return s;
s->flag = CVodeSetLinearSolver(s->cvode_mem, LS, A);
if(check_flag(&s->flag, "CVodeSetLinearSolver", 1)) return s;
It looks like onemkldense solver doesn't have a default difference-quotient jacobian, like the standard dense/band/lapack solvers. Is this true? Users are forced to provide a Jacobian through CVodeSetJacFn to use this solver?
As always thank you very much for your help.
Yes, that's correct. A user-supplied Jacobian function is currently required when using the oneMKL interface. This function may compute the analytic Jacobian or an approximation to it e.g., using difference-quotients.
Why there is not any pre-packaged difference-quotient jacobian as it is for the standard dense solver?
Why there is not any pre-packaged difference-quotient jacobian as it is for the standard dense solver?
The implementation of the difference-quotients routine in CVODE currently is specific to the standard dense and banded matrices. Generalizing it to support other matrices is something that I think would be nice, but we don't currently have any plans to do so.
Thank you for the explanation. This is blocking in my scenario, where I'm translating automatically from MATLAB to C and simulating with sundials by using QSPcc
Can you give me some hints on how to implement a difference-quotient jacobian for the MKL matrix? Thanks
@ciropom: you will need to emulate the code from cvLsDenseDQJac (here), but ensuring that each of the operations use device-resident vector data, and that these operations fill device-resident data within the MKL matrix.
