Intel® oneAPI Math Kernel Library
Ask questions and share information with other developers who use Intel® Math Kernel Library.
6622 Discussions

LAPACKE_dsyevr doesn't finish but LAPACKE_dsyev works well

Ye_C_1
Beginner
204 Views

I have a symmetrc matrix with some parameters to be changed. For some parameters, the LAPACKE_dsyevr does not return for a very long time, so I have to finish the program.

If I change to LAPACKE_dsyev, for most cases, the speed is slower than dsyevr, but the dsyev can return correctly.

What is the reason?

Thanks for your help. 

0 Kudos
3 Replies
Gennady_F_Intel
Moderator
204 Views

What is the problem size when you are calling the dsyevr and finish this execution?  

Ye_C_1
Beginner
204 Views

The dimension of matrix is 10000.

In addition , I still have a question. When we compute the symmetric or Hermitian problem, is it necessary to set the lower part to be all zeros?

If we use the whole matrix as input with both upper and lower part, the result will be wrong? 

Gennady F. (Intel) wrote:

What is the problem size when you are calling the dsyevr and finish this execution?  

Gennady_F_Intel
Moderator
204 Views

 10K - This is plenty small case and you should see the final results of this computations. Could you give us the reproducer to check the problem on our side?

Reply