/// <summary>
/// Generates new students using genetic algorithms.
/// See http://cgg.mff.cuni.cz/~pepca/prg022/luner.html for more details.
/// </summary>
public void DoReproduction()
{
// Sorts students using bubble-sort with respect to rating
int i;
int[] ids = new int[students.Length];
for (int j = 0; j < students.Length; j++)
{
ids[j] = j;
}
bool swaped = true;
while (swaped)
{
swaped = false;
for (i = 0; i < students.Length - 1; i++)
{
if (students[ids[i]].Rating < students[ids[i + 1]].Rating)
{
int temp = ids[i];
ids[i] = ids[i + 1];
ids[i + 1] = temp;
swaped = true;
}
}
}
// First 1/3 mix together
for (i = 0; i < students.Length * 2 / 3; i += 2)
{
// I select two students
Log("Students " + ids[i] + " and " + ids[i + 1] + "has two children");
Gens[] gens = Gens.MixGens(students[ids[i]].Gens, students[ids[i + 1]].Gens);
students[ids[i]] = new Student(this, gens[0]);
students[ids[i + 1]] = new Student(this, gens[1]);
}
// The rest (2/3) is recreated randomly
for (; i < students.Length; i++)
{
students[ids[i]] = new Student(this);
}
Log("New students created");
}
/// <summary>
/// Generates new Gens for genetic algorithm
/// See http://cgg.mff.cuni.cz/~pepca/prg022/luner.html for more details.
/// </summary>
/// <param name="parent1">Mather's gens</param>
/// <param name="parent2">Father's gens</param>
/// <returns>Two element array of gens (two children)</returns>
static public Gens[] MixGens(Gens parent1, Gens parent2)
{
Gens[] result = new Gens[2];
int[] dna1, dna2;
dna1 = parent1.GetCode();
dna2 = parent2.GetCode();
bool translate;
if (Core.rn.Next(100) < 95)
{
translate = true;
}
else
{
translate = false;
}
for (int j = 0; j < GENS_LENGTH; j++)
{
// Translation
if (translate && Core.rn.Next(2) == 0)
{
int temp = dna1[j];
dna1[j] = dna2[j];
dna2[j] = temp;
}
// Random mutation
if (Core.rn.Next(100) < 10)
{
dna1[j] = Core.rn.Next(GENS_MAXS[j]);
}
if (Core.rn.Next(100) < 10)
{
dna2[j] = Core.rn.Next(GENS_MAXS[j]);
}
}
result[0] = new Gens(dna1);
result[1] = new Gens(dna2);
return(result);
}
