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Added new files to the brew, mainly distance and new-op-interface related

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jmerelo 2000-02-07 17:16:16 +00:00
commit 7db1492943
40 changed files with 2490 additions and 992 deletions
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64
eo/src/eoLottery.h
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@ -3,7 +3,7 @@
//-----------------------------------------------------------------------------
// eoLottery.h
// Implements the lottery procedure for selection
// (c) GeNeura Team, 1998
// (c) GeNeura Team, 1998 - Marc Schoenauer, 2000
/*
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
@ -33,53 +33,49 @@
#include <eo> // eoPop eoSelect MINFLOAT
//-----------------------------------------------------------------------------
/// eoLottery: a selection method.
/// requires Chrom::Fitness to be float castable
/** eoLottery: a selection method. Puts into the output a group of individuals
selected using lottery; individuals with higher probability will have more
chances of being selected.
Requires EOT::Fitness to be float castable
*/
//-----------------------------------------------------------------------------
template<class Chrom> class eoLottery: public eoBinPopOp<Chrom>
template<class EOT> class eoLottery: public eoBinPopOp<EOT>
{
public:
/// (Default) Constructor.
eoLottery(const float& _rate = 1.0): rate(_rate) {}
///
void operator()( eoPop<Chrom>& pop, eoPop<Chrom>& breeders)
/** actually selects individuals from pop and pushes them back them into breeders
* until breeders has the right size: rate*pop.size()
* BUT what happens if breeders is already too big?
* Too big for what?
*/
void operator()( eoPop<EOT>& pop, eoPop<EOT>& breeders)
{
// scores of chromosomes
vector<float> score(pop.size());
// calculates accumulated scores for chromosomes
for (unsigned i = 0; i < pop.size(); i++)
// calculates total scores for chromosomes
float total = 0;
for (unsigned i = 0; i < pop.size(); i++) {
score[i] = static_cast<float>(pop[i].fitness());
total += score[i];
}
// number of offspring needed
int target = (int)rint(rate * pop.size());
// test of consistency
if (breeders.size() >= target) {
throw("Problem in eoLottery: already too many offspring");
}
float sum = accumulate(score.begin(), score.end(), MINFLOAT);
transform(score.begin(), score.end(), score.begin(),
bind2nd(divides<float>(), sum));
partial_sum(score.begin(), score.end(), score.begin());
// generates random numbers
vector<float> random(rint(rate * pop.size()));
generate(random.begin(), random.end(), eoUniform<float>(0,1));
sort(random.begin(), random.end(), less<float>());
// selection of chromosomes
unsigned score_index = 0; // position in score vector
unsigned random_index = 0; // position in random vector
while (breeders.size() < random.size())
{
if(random[random_index] < score[score_index])
{
breeders.push_back(pop[score_index]);
random_index++;
}
else
if (score_index < pop.size())
score_index++;
else
fill_n(back_insert_iterator<eoPop<Chrom> >(breeders),
random.size() - breeders.size(), pop.back());
}
while (breeders.size() < target) {
unsigned indloc = rng.roulette_wheel(score, total);
breeders.push_back(pop[indloc]);
}
}
private: