#include "slepcsvd.h" PetscErrorCode SVDSetDimensions(SVD svd,PetscInt nsv,PetscInt ncv,PetscInt mpd)Logically Collective
| svd | - the singular value solver context | |
| nsv | - number of singular values to compute | |
| ncv | - the maximum dimension of the subspace to be used by the solver | |
| mpd | - the maximum dimension allowed for the projected problem |
| -svd_nsv <nsv> | - Sets the number of singular values | |
| -svd_ncv <ncv> | - Sets the dimension of the subspace | |
| -svd_mpd <mpd> | - Sets the maximum projected dimension |
The parameters ncv and mpd are intimately related, so that the user is advised to set one of them at most. Normal usage is that (a) in cases where nsv is small, the user sets ncv (a reasonable default is 2*nsv); and (b) in cases where nsv is large, the user sets mpd.
The value of ncv should always be between nsv and (nsv+mpd), typically ncv=nsv+mpd. If nsv is not too large, mpd=nsv is a reasonable choice, otherwise a smaller value should be used.