MatrixView.h

#ifndef _theplu_yat_utility_matrix_view_
#define _theplu_yat_utility_matrix_view_

// $Id: MatrixView.h 4141 2022-02-01 05:11:36Z peter $

/*
  Copyright (C) 2022 Peter Johansson

  This file is part of the yat library, https://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 <https://www.gnu.org/licenses/>.
*/

#include "config_public.h"

#include "MatrixMutable.h"

#include <gsl/gsl_matrix.h>

#include <cstddef> // size_t

namespace theplu {
namespace yat {
namespace utility {

  class MatrixView : public MatrixMutable
  {
  public:
    MatrixView(void);

    MatrixView(MatrixView& other);

    explicit MatrixView(MatrixMutable& other);

    MatrixView(MatrixMutable& other, size_t row_offset, size_t col_offset,
               size_t rows, size_t columns);

    explicit MatrixView(gsl_matrix* m);

    MatrixView(double* p, size_t rows, size_t cols);

    MatrixView(double* p, size_t rows, size_t cols, size_t tda);

    ~MatrixView(void);

    using MatrixMutable::operator=;

    gsl_matrix* gsl_matrix_p(void);

    const gsl_matrix* gsl_matrix_p(void) const;

    MatrixView& operator=(const MatrixView& other);

  protected:
    void copy_assign(const gsl_matrix* rhs);
    using MatrixMutable::copy_assign;

    void move_assign(MatrixMutable&& rhs);

    void move_assign(gsl_matrix*&& rhs);
  private:
    gsl_matrix_view* view_;
    // create view of data in \c other
    void copy(gsl_matrix* other);
    // create view of data in \c other. Created view has dimension n1
    // x n2 and view(0,0) points to other(k1, k2)
    void copy(gsl_matrix* other, size_t k1, size_t k2, size_t n1, size_t n2);


    // See VectorView::proxy for motivation.
    struct proxy
    {
      proxy(void) = delete;
      proxy(gsl_matrix_view*&& v);
      gsl_matrix_view* view_;
    };

  public:
    MatrixView(proxy p);

    operator proxy();
  };

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

#endif