// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-

//-----------------------------------------------------------------------------
// eoUniformXOver.h
// (c) GeNeura Team, 1998
/* 
    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 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

    Contact: todos@geneura.ugr.es, http://geneura.ugr.es
 */
//-----------------------------------------------------------------------------

#ifndef _EOUNIFORMXOVER_h
#define _EOUNIFORMXOVER_h


// for swap
#if defined( __BORLANDC__ )
#include <algorith>
#else
#include <algorithm>
#endif

// EO includes
#include <eoOp.h>
#include <eoUniform.h>

//-----------------------------------------------------------------------------
/** 
 * EOUniformCrossover: operator for binary chromosomes
 * implementation of uniform crossover for EO
 * swaps ranges of bits between the parents
 */
//-----------------------------------------------------------------------------

template<class EOT> 
class eoUniformXOver: public eoQuadraticOp< EOT >
{
 public:

  ///
  eoUniformXOver( float _rate = 0.5 ): 
    eoQuadraticOp< EOT > (  ), rate( _rate ) {
    if (rate < 0 || rate > 1)
      runtime_error("UxOver --> invalid rate");
  }
  
  
  ///
  void operator() ( EOT& chrom1, EOT& chrom2 ) const {
    unsigned end = min(chrom1.length(),chrom2.length()) - 1;
    // select bits to change
    eoUniform<float> rnd(0, 1);
    
    // aply changes
    for (unsigned bit = 0; bit < end; bit++)
      if (rnd() < rate)
	swap(chrom1[ bit], chrom2[ bit]);
  }

  /** @name Methods from eoObject
      readFrom and printOn are directly inherited from eoOp
  */
  //@{
  /** Inherited from eoObject 
      @see eoObject
  */
  string className() const {return "eoUniformXOver";};
  //@}

private:
  float rate; /// rate of uniform crossover
};

//-----------------------------------------------------------------------------


#endif