#include "slepcnep.h" PetscErrorCode NEPSetWhichEigenpairs(NEP nep,NEPWhich which)Logically Collective
| nep | - eigensolver context obtained from NEPCreate() | |
| which | - the portion of the spectrum to be sought |
| -nep_largest_magnitude | - Sets largest eigenvalues in magnitude | |
| -nep_smallest_magnitude | - Sets smallest eigenvalues in magnitude | |
| -nep_largest_real | - Sets largest real parts | |
| -nep_smallest_real | - Sets smallest real parts | |
| -nep_largest_imaginary | - Sets largest imaginary parts | |
| -nep_smallest_imaginary | - Sets smallest imaginary parts | |
| -nep_target_magnitude | - Sets eigenvalues closest to target | |
| -nep_target_real | - Sets real parts closest to target | |
| -nep_target_imaginary | - Sets imaginary parts closest to target | |
| -nep_all | - Sets all eigenvalues in a region |
| NEP_LARGEST_MAGNITUDE | - largest eigenvalues in magnitude (default) | |
| NEP_SMALLEST_MAGNITUDE | - smallest eigenvalues in magnitude | |
| NEP_LARGEST_REAL | - largest real parts | |
| NEP_SMALLEST_REAL | - smallest real parts | |
| NEP_LARGEST_IMAGINARY | - largest imaginary parts | |
| NEP_SMALLEST_IMAGINARY | - smallest imaginary parts | |
| NEP_TARGET_MAGNITUDE | - eigenvalues closest to the target (in magnitude) | |
| NEP_TARGET_REAL | - eigenvalues with real part closest to target | |
| NEP_TARGET_IMAGINARY | - eigenvalues with imaginary part closest to target | |
| NEP_ALL | - all eigenvalues contained in a given region | |
| NEP_WHICH_USER | - user defined ordering set with NEPSetEigenvalueComparison() |
Not all eigensolvers implemented in NEP account for all the possible values stated above. If SLEPc is compiled for real numbers NEP_LARGEST_IMAGINARY and NEP_SMALLEST_IMAGINARY use the absolute value of the imaginary part for eigenvalue selection.
The target is a scalar value provided with NEPSetTarget().
NEP_ALL is intended for use in the context of the CISS solver for computing all eigenvalues in a region.