several fixes

This commit is contained in:
maartenkeijzer 2007-09-03 14:37:27 +00:00
commit f93327a041
8 changed files with 277 additions and 213 deletions

View file

@ -3,12 +3,18 @@
#include <moo/eoFrontSorter.h>
#include <moo/eoMOEval.h>
#include <cassert>
/** @brief Fast Elitist Non-Dominant Sorting Genetic Algorithm
Variant of the NSGA-II, where the ranking is based on a top-down distance based mechanism ( O(n^2)! )
*/
namespace nsga2a {
extern unsigned assign_worths(std::vector<detail::FitnessInfo> front, unsigned rank, std::vector<double>& worths);
}
template <class EOT>
class eoNSGA_IIa_Eval : public eoMOEval<EOT>
{
@ -24,123 +30,30 @@ class eoNSGA_IIa_Eval : public eoMOEval<EOT>
std::vector<EOT*> pop;
pop.reserve(parents.size() + offspring.size());
for (unsigned i = 0; i < parents.size(); ++i) pop.push_back(&parents[i]);
for (unsigned i = 0; i < offspring.size(); ++i) pop.push_back(&offspring[i]);
for (unsigned i = 0; i < offspring.size(); ++i) {
pop.push_back(&offspring[i]);
}
typename eoFrontSorter<EOT>::front_t front = sorter(pop);
std::vector<double> worths(pop.size());
unsigned rank = pop.size();
for (unsigned i = 0; i < front.size(); ++i) {
rank = assign_worths(front[i], rank, pop);
rank = nsga2a::assign_worths(front[i], rank, worths);
}
for (unsigned i = 0; i < worths.size(); ++i) {
typename EOT::Fitness f = pop[i]->fitness();
f.setWorth(worths[i]);
pop[i]->fitness(f);
}
}
private:
eoFrontSorter<EOT> sorter;
eoFrontSorter<EOT> sorter;
double distance(const std::vector<double>& f1, const std::vector<double>& f2, const std::vector<double>& range) {
double dist = 0;
for (unsigned i = 0; i < f1.size(); ++i) {
double d = (f1[i] - f2[i])/range[i];
dist += d*d;
}
return dist;
}
unsigned assign_worths(const std::vector<detail::FitnessInfo>& front, unsigned rank, std::vector<EOT*>& parents) {
unsigned nDim = front[0].fitness.size();
// find boundary points
std::vector<unsigned> processed(nDim);
for (unsigned i = 1; i < front.size(); ++i) {
for (unsigned dim = 0; dim < nDim; ++dim) {
if (front[i].fitness[dim] > front[processed[dim]].fitness[dim]) {
processed[dim] = i;
}
}
}
// assign fitness to processed
for (unsigned i = 0; i < processed.size(); ++i) {
typename EOT::Fitness f = parents[ front[ processed[i] ].index]->fitness();
f.setWorth(rank);
parents[ front[ processed[i] ].index ]->fitness(f);
}
rank--;
// calculate ranges
std::vector<double> mins(nDim, std::numeric_limits<double>::infinity());
for (unsigned dim = 0; dim < nDim; ++dim) {
for (unsigned i = 0; i < nDim; ++i) {
mins[dim] = std::min( mins[dim], front[ processed[i] ].fitness[dim] );
}
}
std::vector<double> range(nDim);
for (unsigned dim = 0; dim < nDim; ++dim) {
range[dim] = front[ processed[dim] ].fitness[dim] - mins[dim];
}
// calculate distances
std::vector<double> distances(front.size(), std::numeric_limits<double>::infinity());
unsigned selected = 0;
// select based on maximum distance to nearest processed point
for (unsigned i = 0; i < front.size(); ++i) {
for (unsigned k = 0; k < processed.size(); ++k) {
if (i==processed[k]) {
distances[i] = -1.0;
continue;
}
double d = distance( front[i].fitness, front[ processed[k] ].fitness, range );
if (d < distances[i]) {
distances[i] = d;
}
}
if (distances[i] > distances[selected]) {
selected = i;
}
}
while (processed.size() < front.size()) {
// set worth
typename EOT::Fitness f = parents[ front[selected].index ]->fitness();
f.setWorth(rank--);
parents[ front[selected].index ]->fitness(f);
distances[selected] = -1;
processed.push_back(selected);
selected = 0;
for (unsigned i = 0; i < front.size(); ++i) {
if (distances[i] < 0) continue;
double d = distance(front[i].fitness, front[processed.back()].fitness, range);
if (d < distances[i]) {
distances[i] = d;
}
if (distances[i] > distances[selected]) {
selected = i;
}
}
}
return rank;
}
// implementation
};
#endif