slepc-3.21.0 2024-03-30
SVDTRLanczosSetScale
Sets the scale parameter for the GSVD.
Synopsis
#include "slepcsvd.h"
PetscErrorCode SVDTRLanczosSetScale(SVD svd,PetscReal scale)
Logically Collective
Input Parameters
| svd | - singular value solver
|
| scale | - scale parameter
|
Options Database Key
| -svd_trlanczos_scale <real> | - scale factor/threshold
|
Notes
This parameter is relevant for the GSVD case only. If the parameter is
positive, it indicates the scale factor for B in matrix Z=[A;B]. If
negative, its absolute value is the threshold for automatic scaling.
In automatic scaling, whenever the largest approximate generalized singular
value (or the inverse of the smallest value, if SVD_SMALLEST is used)
exceeds the threshold, the computation is restarted with matrix B
scaled by that value.
See Also
SVDTRLanczosGetScale()
Level
advanced
Location
src/svd/impls/trlanczos/trlanczos.c
Examples
src/svd/tutorials/ex51.c
Index of all SVD routines
Table of Contents for all manual pages
Index of all manual pages