source: trunk/yat/normalizer/ColumnNormalizer.h @ 1578

#ifndef _theplu_yat_normalizer_column_normalizer_
#define _theplu_yat_normalizer_column_normalizer_

// $Id: ColumnNormalizer.h 1578 2008-10-14 19:01:02Z peter $

/*
  Copyright (C) 2008 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/>.
*/

#include "yat/utility/Matrix.h"
#include "yat/utility/yat_assert.h"

#include <stdexcept>

namespace theplu {
namespace yat {
namespace normalizer {

  /**
     \brief Using a functor T to normalize each column.

     If the underlying normalizer_type allows normalization "in
     place", i.e., it allows input range and result range to be the
     same range, then it is safe to have same container for input as
     output.
     
     In the case of views and lookups it is more complicated. The
     assignment is done sequentially, so if the input container and
     result container have the same underlying data, the normalization
     is typically not safe.

     \since New in yat 0.5

     \see RowNormalizer
   */
  template<class T>
  class ColumnNormalizer
  {
  public:
    /**
       functor used to normalize each column
    */
    typedef T normalizer_type;

    /**
       \brief Default constructor
     */
    ColumnNormalizer(void) {}

    /**
       \brief Constructor taking a functor \a norm
     */
    ColumnNormalizer(T norm) 
      : normalizer_(norm) {}

    /**
       Each column in \a matrix is normalized using class T, and
       assigned to Matrix \a result.

       Template argument Container2D1 should be a class modelling the
       concept \ref concept_container_2d. The template argument
       Container2D2 should be a class modelling the concept \ref
       concept_mutable_container_2d.

       \note \a result must have same dimensions as \a matrix.
     */
    template<class Container2D1, class Container2D2>
    void operator()(const Container2D1& matrix, Container2D2& result) const
    {
      using utility::yat_assert;
      yat_assert<std::runtime_error>(matrix.rows()==result.rows(),
                                     "ColumnNormalizer: rows mismatch");
      yat_assert<std::runtime_error>(matrix.columns()==result.columns(),
                                     "ColumnNormalizer: columns mismatch");
      for (size_t i=0; i<matrix.columns(); ++i)
        normalizer_(matrix.begin_column(i), matrix.end_column(i),
                    result.begin_column(i));
      
    }

  private:
    T normalizer_;
  };

}}} // end of namespace normalizer, yat and thep
#endif