EuclideanDistance.h

#ifndef theplu_yat_statistics_euclidean_distance_h
#define theplu_yat_statistics_euclidean_distance_h

// $Id: EuclideanDistance.h 3550 2017-01-03 05:41:02Z peter $

/*
  Copyright (C) 2007, 2008 Jari Häkkinen, Peter Johansson, Markus Ringnér
  Copyright (C) 2010, 2016 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 "AveragerPair.h"
#include "AveragerPairWeighted.h"
#include "Distance.h"

#include <cmath>

namespace theplu {
namespace yat {
namespace statistics {

  class EuclideanDistance : public Distance<EuclideanDistance>
  {
  private:
    friend class Distance<EuclideanDistance>;

    template <typename Iter1, typename Iter2>
    double distance (Iter1 beg1,Iter1 end1, Iter2 beg2,
                     utility::unweighted_iterator_tag) const
    {
      AveragerPair ap;
      add(ap,beg1,end1,beg2);
      return sqrt(ap.sum_squared_deviation());
    }

    template <typename Iter1, typename Iter2>
    double distance (Iter1 beg1,Iter1 end1, Iter2 beg2,
                     utility::weighted_iterator_tag) const
    {
      AveragerPairWeighted ap;
      add(ap,beg1,end1,beg2);
      return sqrt(std::distance(beg1,end1)*ap.msd());
    }

  };

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

#endif