?xml version="1.0" encoding="UTF-8"?> Special Products - 1.64.0

Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for an old version of Boost. Click here to view this page for the latest version.

Special Products

Functions

template<class V, class E1, class E2> BOOST_UBLAS_INLINE V &  axpy_prod (const matrix_expression< E1 > &e1, const vector_expression< E2 > &e2, V &v, bool init=true)
  computes v += A x or v = A x in an optimized fashion.

template<class V, class E1, class E2> BOOST_UBLAS_INLINE V &  axpy_prod (const vector_expression< E1 > &e1, const matrix_expression< E2 > &e2, V &v, bool init=true)
  computes v += AT x or v = AT x in an optimized fashion.

template<class M, class E1, class E2> BOOST_UBLAS_INLINE M &  axpy_prod (const matrix_expression< E1 > &e1, const matrix_expression< E2 > &e2, M &m, bool init=true)
  computes M += A X or M = A X in an optimized fashion.

template<class M, class E1, class E2> BOOST_UBLAS_INLINE M &  opb_prod (const matrix_expression< E1 > &e1, const matrix_expression< E2 > &e2, M &m, bool init=true)
  computes M += A X or M = A X in an optimized fashion.


BOOST_UBLAS_INLINE V& axpy_prod const matrix_expression< E1 > &  e1,
const vector_expression< E2 > &  e2,
V &  v,
bool  init = true
 

computes v += A x or v = A x in an optimized fashion.

Parameters:
e1 the matrix expression A
e2 the vector expression x
v the result vector v
init a boolean parameter
axpy_prod(A, x, v, init) implements the well known axpy-product. Setting init to true is equivalent to call v.clear() before axpy_prod. Currently init defaults to true, but this may change in the future.

Up to now there are some specialisation for compressed matrices that give a large speed up compared to prod.

BOOST_UBLAS_INLINE V& axpy_prod const vector_expression< E1 > &  e1,
const matrix_expression< E2 > &  e2,
V &  v,
bool  init = true
 

computes v += AT x or v = AT x in an optimized fashion.

Parameters:
e1 the vector expression x
e2 the matrix expression A
v the result vector v
init a boolean parameter
axpy_prod(x, A, v, init) implements the well known axpy-product. Setting init to true is equivalent to call v.clear() before axpy_prod. Currently init defaults to true, but this may change in the future.

Up to now there are some specialisation for compressed matrices that give a large speed up compared to prod.

BOOST_UBLAS_INLINE M& axpy_prod const matrix_expression< E1 > &  e1,
const matrix_expression< E2 > &  e2,
M &  m,
bool  init = true
 

computes M += A X or M = A X in an optimized fashion.

Parameters:
e1 the matrix expression A
e2 the matrix expression X
m the result matrix M
init a boolean parameter
axpy_prod(A, X, M, init) implements the well known axpy-product. Setting init to true is equivalent to call M.clear() before axpy_prod. Currently init defaults to true, but this may change in the future.

Up to now there are no specialisations.

BOOST_UBLAS_INLINE M& opb_prod const matrix_expression< E1 > &  e1,
const matrix_expression< E2 > &  e2,
M &  m,
bool  init = true
 

computes M += A X or M = A X in an optimized fashion.

Parameters:
e1 the matrix expression A
e2 the matrix expression X
m the result matrix M
init a boolean parameter
opb_prod(A, X, M, init) implements the well known axpy-product. Setting init to true is equivalent to call M.clear() before opb_prod. Currently init defaults to true, but this may change in the future.

This function may give a speedup if A has less columns than rows, because the product is computed as a sum of outer products.


Copyright (©) 2000-2004 Michael Stevens, Mathias Koch, Joerg Walter, Gunter Winkler
Use, modification and distribution are subject to the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt ).