private void MultiStdDevMutation(ref ESSolution offspring)
{
SafeDebug.AssertNotNull(offspring, "offspring != null");
base.modelBuilder = base.context.CreateArithmeticModelBuilder(offspring.currentModel);
double globalLearningRate = (double)1 / Math.Sqrt((double)2 * (double)base.context.Variables.Count <IArithmeticVariable>());
double localLearningRate = (double)1 / Math.Sqrt((double)2 * Math.Sqrt((double)base.context.Variables.Count <IArithmeticVariable>()));
double overallT = globalLearningRate * Gaussian(0, 1);
int index = 0;
foreach (var variable in base.context.Variables)
{
Term sum = null;
double ni = overallT + localLearningRate * Gaussian(0, 1);
double scaleFactor = offspring.GetStdDev(index) * Math.Exp(ni);
offspring.SetStdDev(index, scaleFactor);
bool success = TryAddDoubleToTerm(variable.Term, scaleFactor * Gaussian(0, 1), out sum);
if (success)
{
base.modelBuilder.TryAssign(variable, offspring.currentModel.GetValue(sum));
}
index++;
}
offspring.UpdateModel(base.modelBuilder.ToArithmeticModel());
}
private void GlobalDiscreteRecombination(ref ESSolution offspring)
{
int index1, index2;
ESSolution parent1 = null;
ESSolution parent2 = null;
int index = 0;
offspring = new ESSolution(this, this.variableCount);
foreach (var variable in base.context.Variables)
{
GenerateTwoIndeces(out index1, out index2);
parent1 = this.parentPopulation[index1];
parent2 = this.parentPopulation[index2];
if (base.random.Next(0, 2) == 0)
{
base.modelBuilder.TryAssign(variable, parent1.currentModel.GetValue(variable.Term));
offspring.SetStdDev(index, parent1.GetStdDev(index));
}
else
{
base.modelBuilder.TryAssign(variable, parent2.currentModel.GetValue(variable.Term));
offspring.SetStdDev(index, parent2.GetStdDev(index));
}
index++;
}
offspring.UpdateModel(base.modelBuilder.ToArithmeticModel());
}
private void GlobalIntermediateRecombination(ref ESSolution offspring)
{
int index1, index2;
ESSolution parent1 = null;
ESSolution parent2 = null;
offspring = new ESSolution(this, this.variableCount);
Term sum = null;
int index = 0;
foreach (var variable in base.context.Variables)
{
GenerateTwoIndeces(out index1, out index2);
parent1 = this.parentPopulation[index1];
parent2 = this.parentPopulation[index2];
sum = base.termManager.Add(parent1.currentModel.GetValue(variable.Term),
parent2.currentModel.GetValue(variable.Term));
base.modelBuilder.TryAssign(variable, DivideByTwo(sum));
double stdDev1 = parent1.GetStdDev(index);
double stdDev2 = parent2.GetStdDev(index);
offspring.SetStdDev(index, (0.5 * (stdDev1 + stdDev2)));
index++;
}
offspring.UpdateModel(base.modelBuilder.ToArithmeticModel());
}
private void SingleStdDevMutation(ref ESSolution offspring)
{
SafeDebug.AssertNotNull(offspring, "offspring != null");
base.modelBuilder = base.context.CreateArithmeticModelBuilder(offspring.currentModel);
double learningRate = (double)1 / Math.Sqrt((double)base.context.Variables.Count <IArithmeticVariable>());
double stdDev = offspring.GetStdDev(0) * Math.Exp(learningRate * Gaussian(0, 1));
offspring.SetStdDev(0, stdDev);
foreach (var variable in base.context.Variables)
{
Term sum = null;
bool success = TryAddDoubleToTerm(variable.Term, stdDev * Gaussian(0, 1), out sum);
if (success)
{
base.modelBuilder.TryAssign(variable, offspring.currentModel.GetValue(sum));
}
}
offspring.UpdateModel(base.modelBuilder.ToArithmeticModel());
}
private void DiscreteRecombination(ref ESSolution offspring)
{
int index1, index2;
int index = 0;
GenerateTwoIndeces(out index1, out index2);
ESSolution parent1 = this.parentPopulation[index1];
ESSolution parent2 = this.parentPopulation[index2];
offspring = parent1.MakeDeepCopy();
foreach (var variable in base.context.Variables)
{
if (base.random.Next(0, 2) != 0)
{
base.modelBuilder.TryAssign(variable, parent2.currentModel.GetValue(variable.Term));
offspring.SetStdDev(index, parent2.GetStdDev(index));
}
index++;
}
offspring.UpdateModel(base.modelBuilder.ToArithmeticModel());
}
