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

//-----------------------------------------------------------------------------
// eoAtomCreep.h
//   Increments or decrements by one a single element
// (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 _EOATOMCREEP_H
#define _EOATOMCREEP_H

#include <utils/eoRNG.h>
#include <eoAtomMutator.h>

/** With uniform probability, decrements or increments by one the value.
    The value type must admit post increment and decrement.
*/
template <class T>
class eoAtomCreep: public eoAtomMutator<T> {
public:

  /// 
  eoAtomCreep() {};
  
  ///
  virtual ~eoAtomCreep() {};
  
  ///
  virtual void operator()( T& _val ) const {
    if ( rng.flip( 0.5 ) ) {
      _val++;
    } else {
      _val--;
    }
  }
  
  /** @name Methods from eoObject
  */  
  //@{
  /** Inherited from eoObject 
      @see eoObject
  */
  virtual string className() const {return "eoAtomCreep";};
  //@}

};


#endif