I am new to Fortran intel MKL. I am trying to use the FGMRES with ILUT preconditioner for solving the Penta diagonal matrix (A*x=b.) resulting from discretization of 3D convection-diffusion equation. The coefficient matrix is naturally stored in a band format.
Since ILUT is using CSR storage, how can I convert the band storage format to CSR format?
Also, for matrix-vector multiplication step, for my case do I have to multiply inv(A)*b? I am confused about this.