TransposedMatrix.h

#ifndef _theplu_yat_utility_expression_transposed_matrix
#define _theplu_yat_utility_expression_transposed_matrix

// $Id: TransposedMatrix.h 3908 2020-05-13 06:58:38Z peter $

/*
  Copyright (C) 2020 Peter Johansson

  This file is part of the yat library, http://dev.thep.lu.se/yat

  The yat library is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 3 of the
  License, or (at your option) any later version.

  The yat 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
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with yat. If not, see <http://www.gnu.org/licenses/>.
*/


namespace theplu {
namespace yat {
namespace utility {
namespace expression {


  template<class T>
  class TransposedMatrix : public MatrixExpression<TransposedMatrix<T> >
  {
  public:
    TransposedMatrix(const BasicMatrix<T>& A)
      : A_(A) {}

    size_t rows(void) const { return A_.columns(); }
    size_t columns(void) const { return A_.rows(); }

    double operator()(size_t i, size_t j) const
    {
      return A_(j, i);
    }

    void calculate_matrix(gsl_matrix*& result) const
    {
      detail::reallocate(result, rows(), columns());
      gsl_matrix_transpose_memcpy(result, A_.gsl_matrix_p());
    }

    const T& base(void) const
    {
      return static_cast<const T&>(A_);
    }

  private:
    const BasicMatrix<T>& A_;
  };


}}}} // of namespace expression, utility, yat, and theplu

#endif