I am running the given example: FreeFem-sources/navier-stokes-2d-SLEPc-complex.edp at develop · FreeFem/FreeFem-sources · GitHub.

This solved example uses “PETSc-complex”.

This problem works with the following:

string params = "-eps_tol 1.0e-6 -eps_nev " + nev + " " +

"-eps_type krylovschur -st_type sinvert -eps_monitor_all " +

"-eps_target " + real(s) + “+” + imag(s) + “i”;

I followed the given SLEPc documentation: https://slepc.upv.es/documentation/slepc.pdf.

In the SLEPc documentation, there are options like: -eps_largest_magnitude, -eps_smallest_magnitude, -eps_smallest_real, etc. These three are used as follows:

string params = "-eps_tol 1.0e-10 -eps_nev " + nev + " " +

"-eps_type krylovschur -eps_largest_magnitude -eps_monitor_all ";

int k = EPSSolve(J, M, vectors = vec, values = val, sparams = params);

The following error came:

string params = "-eps_tol 1.0e-10 -eps_nev " + nev + " " +

"-eps_type krylovschur -eps_smallest_magnitude -eps_monitor_all ";

int k = EPSSolve(J, M, vectors = vec, values = val, sparams = params);

The following error came:

string params = "-eps_tol 1.0e-10 -eps_nev " + nev + " " +

"-eps_type krylovschur -eps_smallest_real -eps_monitor_all ";

int k = EPSSolve(J, M, vectors = vec, values = val, sparams = params);

The following error came:

I am using FreeFEM version 4.9 on Windows 10. I do not understand if the option “-st_type sinvert” is working successfully, why SLEPc options such as “-eps_largest_magnitude”, “-eps_smallest_magnitude”, and “-eps_smallest_real” are giving error.