Dear all,
I want to calculate k smallest eigenvalues of a large sparse matrix (1e6*1e6), and the only solver I can find to finish this task is LOBPCG from MAGMA, which can solve the largest and smallest eigenvalues. However, I couldn't find some certain parameter to determine to solve whether largest or smallest k eigenvalues. Could you please tell me how to set parameters to calculate only k smallest eigenvalues of a large sparse matrix? I know that num_eigenvaluses in solver_par is the k number of EV for eigensovers, but I didn't find documation about sparse precond_par parameters. Is there some parameters that I didn't notice?
Best regards,
Shiyun