slepc-3.20.2 2024-03-15
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BVCreateTensor

Creates a tensor BV that is represented in compact form as V = (I otimes U) S, where U has orthonormal columns.

Synopsis

#include "slepcbv.h" 
PetscErrorCode BVCreateTensor(BV U,PetscInt d,BV *V)
Collective

Input Parameters

U  - a basis vectors object
d  - the number of blocks (degree) of the tensor BV

Output Parameter

V  - the new basis vectors context

Notes

The new basis vectors object is V = (I otimes U) S, where otimes denotes the Kronecker product, I is the identity matrix of order d, and S is a sequential matrix allocated internally. This compact representation is used e.g. to represent the Krylov basis generated with the linearization of a matrix polynomial of degree d.

The size of V (number of rows) is equal to d times n, where n is the size of U. The dimensions of S are d times m rows and m-d+1 columns, where m is the number of columns of U, so m should be at least d.

The communicator of V will be the same as U.

On input, the content of U is irrelevant. Alternatively, it may contain some nonzero columns that will be used by BVTensorBuildFirstColumn().

See Also

BVTensorGetDegree(), BVTensorGetFactors(), BVTensorBuildFirstColumn()

Level

advanced

Location

src/sys/classes/bv/impls/tensor/bvtensor.c

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