//Initializes Population and their memories.
public List<Dilemma> RampedHalfAndHalfInitialization(int populationsize, int memorylength)
{
List<Dilemma> population = new List<Dilemma>();
for(int i = 0; i < populationsize; i++)
{
int fullorgrow = RandomGenerator.Next(0, 2);
Dilemma newdilemma = new Dilemma();
newdilemma.GenerateUniformRandomMemory(memorylength, RandomGenerator);
//Full Method
if(fullorgrow == 0)
{
newdilemma.Tree = GenerateNewUniformRandomTreeFull(config.MaxTreeDepth, 1, newdilemma.Memory, RandomGenerator, treepossibilities);
population.Add(newdilemma);
}
//Grow Method
else
{
newdilemma.Tree = GenerateNewUniformRandomTreeGrow(config.MaxTreeDepth, 1, newdilemma.Memory, RandomGenerator, treepossibilities);
population.Add(newdilemma);
}
}
return population;
}
//Play the IPD, evaluating fitness for sequencelength - 2 * memorylength
public void PlayIPD(ref Dilemma dilemma1, ref Dilemma dilemma2, int sequencelength, double parsimonypressure, int maxtreedepth, int memorylength)
{
dilemma1.GenerateUniformRandomMemory(memorylength, RandomGenerator);
dilemma2.GenerateUniformRandomMemory(memorylength, RandomGenerator);
double fitness1 = 0.0;
double fitness2 = 0.0;
for(int i = 0; i < sequencelength; i++)
{
if (i >= 2 * memorylength)
{
//Add to total fitness
fitness1 += (double)SingleFitnessCalculation(dilemma1.Tree.GetValue(dilemma1.Memory), dilemma2.Tree.GetValue(dilemma2.Memory));
fitness2 += (double)SingleFitnessCalculation(dilemma2.Tree.GetValue(dilemma2.Memory), dilemma1.Tree.GetValue(dilemma1.Memory));
}
//Place it in memory
dilemma1.Memory.Enqueue(new bool[2] { dilemma1.Tree.GetValue(dilemma1.Memory), dilemma2.Tree.GetValue(dilemma2.Memory) });
dilemma2.Memory.Enqueue(new bool[2] { dilemma2.Tree.GetValue(dilemma2.Memory), dilemma1.Tree.GetValue(dilemma1.Memory) });
//If the memory is bigger than is allowed, pop the shiz.
if(dilemma1.Memory.Count > memorylength)
{
dilemma1.Memory.Dequeue();
}
if(dilemma2.Memory.Count > memorylength)
{
dilemma2.Memory.Dequeue();
}
}
fitness1 /= ((double)sequencelength - 2.0 * (double)memorylength);
fitness2 /= ((double)sequencelength - 2.0 * (double)memorylength);
//Parsimony pressure:
//Fitness = Fitness - Fitness * Parsimony Pressure * (Tree Size / Max Tree Size)
//Parsimony Pressure is a double between 0.0 and 1.0.
//Max tree size is 2^(Max Tree Depth) + 1
fitness1 -= (fitness1 * (parsimonypressure * (double)dilemma1.Tree.Size / (double)((2<<maxtreedepth) + 1)));
fitness2 -= (fitness2 * (parsimonypressure * (double)dilemma2.Tree.Size / (double)((2<<maxtreedepth) + 1)));
dilemma1.Fitness += fitness1;
dilemma2.Fitness += fitness2;
fitnessevals++;
}