Prototype

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

larft( const char direct, const char storev, const int_t n,
        const int_t k, MatrixV& v, const VectorTAU& tau,
        MatrixT& t );

Description

larft (short for $FRIENDLY_NAME) provides a C++ interface to LAPACK routines SLARFT, DLARFT, CLARFT, and ZLARFT. larft forms the triangular factor T of a complex block reflector H of order n, which is defined as a product of k elementary reflectors.

If DIRECT = 'F', H = H(1) H(2) . . . H(k) and T is upper triangular;

If DIRECT = 'B', H = H(k) . . . H(2) H(1) and T is lower triangular.

If STOREV = 'C', the vector which defines the elementary reflector H(i) is stored in the i-th column of the array V, and

H = I - V * T * V'

If STOREV = 'R', the vector which defines the elementary reflector H(i) is stored in the i-th row of the array V, and

H = I - V' * T * V

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

Definition

Defined in header boost/numeric/bindings/lapack/auxiliary/larft.hpp.

Parameters or Requirements on Types

Complexity

Example

#include <boost/numeric/bindings/lapack/auxiliary/larft.hpp>
using namespace boost::numeric::bindings;

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

this will output

[5] 0 1 2 3 4 5

Notes

See Also