paradiseo/deprecated/eo/src/utils/eoDistance.h

104 lines
2.8 KiB
C++

// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-
//-----------------------------------------------------------------------------
// eoDistance.h
// (c) GeNeura Team, 1998, Marc Schoenauer 2001
/*
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
Marc.Schoenauer@polytechnique.fr
*/
//-----------------------------------------------------------------------------
#ifndef _eoDistance_H
#define _eoDistance_H
#include <eoFunctor.h>
/** @addtogroup Stats
* @{
* */
/**
This is a generic class for distance functors:
takes 2 things and returns a double
*/
template< class EOT >
class eoDistance : public eoBF<const EOT &, const EOT &, double>
{};
/**
This is a generic class for Euclidain distance (L2 norm) computation:
assumes the 2 things are std::vectors of something that is double-castable
*/
template< class EOT >
class eoQuadDistance : public eoDistance<EOT>
{
public:
double operator()(const EOT & _v1, const EOT & _v2)
{
double sum=0.0;
for (unsigned i=0; i<_v1.size(); i++)
{
double r = static_cast<double> (_v1[i]) - static_cast<double> (_v2[i]);
sum += r*r;
}
return sqrt(sum);
}
};
/**
This is a generic class for L1 distance computation:
assumes the 2 things are std::vectors of something
that is double-castable
For bitstrings, this is the Hamming distance
*/
template< class EOT >
class eoHammingDistance : public eoDistance<EOT>
{
public:
double operator()(const EOT & _v1, const EOT & _v2)
{
double sum=0.0;
for (unsigned i=0; i<_v1.size(); i++)
{
double r = static_cast<double> (_v1[i]) - static_cast<double> (_v2[i]);
sum += fabs(r);
}
return sum;
}
};
/* this distance measures the difference in fitness
* I am not sure it can be of any use, though ...
* except for some testing
*/
template< class EOT >
class eoFitnessDistance : public eoDistance<EOT>
{
public:
double operator()(const EOT & _v1, const EOT & _v2)
{
double d = _v1.fitness() - _v2.fitness();
return sqrt(d*d);
}
};
/** @} */
#endif