slepc-main 2024-11-15
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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