private void Selection(double crysisPower, Random random, Settings settings)
{
List <Tuple <double, double> > survivabilityByAge = new List <Tuple <double, double> >();
List <Species> survivors = new List <Species>(this.m_speciesList.Count);
List <Species> victims = new List <Species>(this.m_speciesList.Count);
int maxAge = 0;
foreach (Species species in this.m_speciesList)
{
double survivability;
double survivalProbability = species.GetSurvivalProbability(crysisPower, settings.SurvivabilityToSurvivalProbabilityTransfrom, out survivability);
survivabilityByAge.Add(Tuple.Create((double)species.age, survivability));
if (random.ProbCheck(survivalProbability))
{
survivors.Add(species);
}
else
{
victims.Add(species);
}
if (species.age > maxAge)
{
maxAge = species.age;
}
}
if (m_speciesList.Count > 0)
{
this.MortalityRate = 1.0 * (m_speciesList.Count - survivors.Count) / m_speciesList.Count;
}
else
{
this.MortalityRate = 0;
}
this.m_speciesList = survivors;
this.SurvivabilityStats = new Stats(survivabilityByAge.Select(item => item.Item2));
this.AgeAtDeathStats = new Stats(victims.Select(item => (double)item.age));
this.SurvivabilityByAgeStats = new Stats2D(0, maxAge, 1, survivabilityByAge);
}
private void Breeding(Random random, Settings settings, double crysisPower)
{
List <Species> parents = new List <Species>(this.m_speciesList.Count);
double matingProbability = settings.PopulationSizeToMatingProbabilityTransform(this.m_speciesList.Count);
foreach (Species species in this.m_speciesList)
{
if (random.ProbCheck(matingProbability))
{
parents.Add(species);
}
}
List <Species> offsprings = new List <Species>();
if (settings.SexualReproduction)
{
if (parents.Count > 1)
{
switch (settings.MatingStrategy)
{
case Settings.MatingStrategyType.Random:
random.Shuffle(parents);
for (int i = 0; i < parents.Count; i += 2)
{
Species parent1 = parents[i];
int j = i + 1;
if (j >= parents.Count)
{
j = 0;
}
Species parent2 = parents[j];
Species offspring = Species.CreateOffspringSex(parent1, parent2, random, settings);
offsprings.Add(offspring);
}
break;
case Settings.MatingStrategyType.PositiveAssortion:
parents = parents.OrderByDescending(item => item.GetSurvivability(crysisPower)).ToList(); //descending because we'll be taking last from list as it's much faster
{
double maxCunning = parents.Max(item => item.cunning);
double maxAgeingSpeed = parents.Max(item => item.ageingSpeed);
while (parents.Count > 2)
{
Species parent1 = parents[parents.Count - 1];
parents.RemoveAt(parents.Count - 1);
int bestPartnerIndex = 0;
double bestPartnerDistance = SimilarityDistanceSquared(parent1, parents[bestPartnerIndex], maxCunning, maxAgeingSpeed);
for (int i = 1; i < parents.Count; ++i)
{
double distance = SimilarityDistanceSquared(parent1, parents[i], maxCunning, maxAgeingSpeed);
if (distance < bestPartnerDistance)
{
bestPartnerDistance = distance;
bestPartnerIndex = i;
}
}
Species parent2 = parents[bestPartnerIndex];
parents.RemoveAt(bestPartnerIndex);
Species offspring = Species.CreateOffspringSex(parent1, parent2, random, settings);
offsprings.Add(offspring);
}
}
break;
default:
throw new ApplicationException("Unexpected strategy " + settings.MatingStrategy);
}
}
}
else
{
foreach (Species parent in parents)
{
Species offspring = Species.CreateOffspringReplication(parent, random, settings);
offsprings.Add(offspring);
}
}
if (m_speciesList.Count > 0)
{
this.RateOfOrigination = 1.0 * (offsprings.Count) / m_speciesList.Count;
}
else
{
this.RateOfOrigination = 0;
}
this.m_speciesList.AddRange(offsprings);
this.CunningHistogramm = Stats2D.CreateForCounts(0, settings.MaximalCunning, 0.25, m_speciesList.Select(item => item.cunning));
}