SVDCrossSetExplicitMatrix — SLEPc 3.24.2 documentation

Skip to main content
`Ctrl`+`K`

# SVDCrossSetExplicitMatrix

Indicate if the eigensolver operator \(A^*A\) must be computed explicitly.

## Synopsis

    #include "slepcsvd.h"
    PetscErrorCode SVDCrossSetExplicitMatrix(SVD svd,PetscBool explicitmat)

Logically Collective

## Input Parameters

- svd - the singular value solver context

- explicitmat - `PETSC_TRUE` if \(A^*A\) must be built explicitly

## Options Database Key

- -svd_cross_explicitmatrix - toggle the explicit construction of the matrix

## Notes

In GSVD there are two cross product matrices, \(A^*A\) and \(B^*B\). In HSVD the expression for the cross product matrix is different, \(A^*\Omega A\). See Mathematical Background for details.

By default the matrices are not built explicitly, but handled as shell matrices, see `MATSHELL`.

## See Also

SVD: Singular Value Decomposition, Mathematical Background, `SVDCROSS`, `SVDCrossGetExplicitMatrix()`, `MATSHELL`

## Level

advanced

## Location

src/svd/impls/cross/cross.c

## Implementations

SVDCrossSetExplicitMatrix_Cross() in src/svd/impls/cross/cross.c

Index of all SVD routines Table of Contents for all manual pages Index of all manual pages