Prototype

There is one prototype of gejsv available, please see below.

gejsv( const char joba, const char jobu, const char jobv,
        const char jobr, const char jobt, const char jobp, MatrixA& a,
        VectorSVA& sva, MatrixU& u, MatrixV& v );

Description

gejsv (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SGEJSV and DGEJSV. gejsv computes the singular value decomposition (SVD) of a real M-by-N matrix [A], where M >= N. The SVD of [A] is written as

[A] = [U] * [SIGMA] * [V]^t,

where [SIGMA] is an N-by-N (M-by-N) matrix which is zero except for its N diagonal elements, [U] is an M-by-N (or M-by-M) orthonormal matrix, and [V] is an N-by-N orthogonal matrix. The diagonal elements of [SIGMA] are the singular values of [A]. The columns of [U] and [V] are the left and the right singular vectors of [A], respectively. The matrices [U] and [V] are computed and stored in the arrays U and V, respectively. The diagonal of [SIGMA] is computed and stored in the array SVA.

The selection of the LAPACK routine is done during compile-time, and is determined by the type of values contained in type MatrixA. The type of values is obtained through the value_type meta-function typename value_type<MatrixA>::type. The dispatching table below illustrates to which specific routine the code path will be generated.

Definition

Defined in header boost/numeric/bindings/lapack/driver/gejsv.hpp.

Parameters or Requirements on Types

Complexity

Example

#include <boost/numeric/bindings/lapack/driver/gejsv.hpp>
using namespace boost::numeric::bindings;

lapack::gejsv( x, y, z );

this will output

[5] 0 1 2 3 4 5

Notes

See Also