public void TournamentParentSelection_VerifySelectionProbability()
{
// Test tournament selection by comparing it to the old "established" tournament selection implementation.
var random = new DefaultRandomNumberGenerator("seed".GetHashCode());
for (int tournamentSize = 2; tournamentSize <= 10; tournamentSize++)
{
var population = new Population(11);
var index = 0;
population.Fill(() => new TestPhenotype(index++, index * index));
population.Sort(EAMode.MaximizeFitness);
var config = new EAConfiguration
{
TournamentSize = 3,
TournamentProbability = 0.5
};
#pragma warning disable CS0618 // Type or member is obsolete
var oldselection = new TournamentParentSelectionOld(config);
#pragma warning restore CS0618 // Type or member is obsolete
var oldselected = oldselection.SelectParents(population, 275000, EAMode.MaximizeFitness, random);
foreach (var(a, b) in oldselected)
{
((TestPhenotype)a).Count2++;
((TestPhenotype)b).Count2++;
}
var selection = new TournamentParentSelection(config);
var selected = selection.SelectParents(population, 275000, EAMode.MaximizeFitness, random);
foreach (var(a, b) in selected)
{
((TestPhenotype)a).Count++;
((TestPhenotype)b).Count++;
}
var counts = population.Cast <TestPhenotype>().Select(p => p.Count).Zip(population.Cast <TestPhenotype>().Select(p => p.Count2), (c1, c2) => (c1, c2));
foreach (var count in counts)
{
(count.c1 - count.c2).Should().BeLessThan(1000, $"tournament size = {tournamentSize}");
}
}
}
public void TournamentSelection_PerfTest()
{
var random = new DefaultRandomNumberGenerator();
var config = new EAConfiguration
{
TournamentSize = 20,
TournamentProbability = 0.5
};
var popsize = 10000;
var pop = new Population(popsize);
pop.Fill(() => CreatePhenotypeMock(random.NextDouble() * 10).Object);
pop.Sort(EAMode.MaximizeFitness);
Console.WriteLine($"popsize = {popsize}, tournament size = {config.TournamentSize}");
var watch = new Stopwatch();
watch.Start();
#pragma warning disable CS0618 // Type or member is obsolete
IParentSelection selection = new TournamentParentSelectionOld(config);
#pragma warning restore CS0618 // Type or member is obsolete
foreach (var selected in selection.SelectParents(pop, popsize, EAMode.MaximizeFitness, random))
{
}
watch.Stop();
Console.WriteLine($"old: {watch.ElapsedMilliseconds} ms");
watch.Restart();
selection = new TournamentParentSelection(config);
foreach (var selected in selection.SelectParents(pop, popsize, EAMode.MaximizeFitness, random))
{
}
watch.Stop();
Console.WriteLine($"new: {watch.ElapsedMilliseconds} ms");
}