Files
eigen/tvmet-1.7.1/include/tvmet/loop/Gemmt.h
Benoit Jacob 6d749c172a replace size_t with int everywhere.
The size_t type means a number of _bytes_, and it was misused as
counting e.g. the number of rows/columns in a matrix. Moreover, it is unsigned,
which can give strange bugs if a signed/unsigned mismatch occurs.
2007-06-01 07:56:24 +00:00

115 lines
3.0 KiB
C++

/*
* Tiny Vector Matrix Library
* Dense Vector Matrix Libary of Tiny size using Expression Templates
*
* Copyright (C) 2001 - 2003 Olaf Petzold <opetzold@users.sourceforge.net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: Gemmt.h,v 1.5 2004/06/16 09:30:07 opetzold Exp $
*/
#ifndef TVMET_LOOP_GEMMT_H
#define TVMET_LOOP_GEMMT_H
namespace tvmet {
namespace loop {
/**
* \class gemmt Gemmt.h "tvmet/loop/Gemmt.h"
* \brief class for for product matrix-transpose(matrix) operations.
* using formula
* \f[
* M_1\,M_2^{T}
* \f]
* \par Example:
* \code
* template<class T, int Rows1, int Cols1, int Cols2>
* inline
* void
* prod(const Matrix<T, Rows1, Cols1>& lhs, const Matrix<T, Rows2, Cols1>& rhs,
* Matrix<T, Rows1, Rows2>& dest)
* {
* for (int i = 0; i != Rows1; ++i) {
* for (int j = 0; j != Rows2; ++j) {
* dest(i, j) = tvmet::loop::gemmt<Rows1, Cols1, Cols1>().prod(lhs, rhs, i, j);
* }
* }
* }
* \endcode
* \note The number of cols of rhs matrix have to be equal to cols of rhs matrix.
* The result is a (Rows1 x Rows2) matrix.
*/
template<int Rows1, int Cols1,
int Cols2 /* unused */>
class gemmt
{
gemmt(const gemmt&);
gemmt& operator=(const gemmt&);
private:
enum {
count = Cols1,
N = (count+7)/8
};
public:
gemmt() { }
public:
template<class E1, class E2>
static inline
typename PromoteTraits<
typename E1::value_type,
typename E2::value_type
>::value_type
prod(const E1& lhs, const E2& rhs, int i, int j) {
typename PromoteTraits<
typename E1::value_type,
typename E2::value_type
>::value_type sum(0);
int k(0);
int n(N);
// Duff's device
switch(count % 8) {
case 0: do { sum += lhs(i, k) * rhs(j, k); ++k;
case 7: sum += lhs(i, k) * rhs(j, k); ++k;
case 6: sum += lhs(i, k) * rhs(j, k); ++k;
case 5: sum += lhs(i, k) * rhs(j, k); ++k;
case 4: sum += lhs(i, k) * rhs(j, k); ++k;
case 3: sum += lhs(i, k) * rhs(j, k); ++k;
case 2: sum += lhs(i, k) * rhs(j, k); ++k;
case 1: sum += lhs(i, k) * rhs(j, k); ++k;
} while(--n != 0);
}
return sum;
}
};
} // namespace loop
} // namespace tvmet
#endif /* TVMET_LOOP_GEMMT_H */
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