// Makes new chromosome with same setup but with randomly chosen code
public Schedule MakeNewFromPrototype()
{
// number of time-space slots
int size = Slots.Count;
//// make new chromosome, copy chromosome setup
Schedule newChromosome = new Schedule(this, true);
// place classes at random position
List<CourseClass> c = Configuration.Instance.CourseClasses;
foreach (var courseClass in c)
{
// determine random position of class
int nr = Configuration.Instance.GetNumberOfRooms();
int duration = courseClass.LessonDuration;
int day = random.Next(0, Consts.DayCount);
int room = random.Next(0, nr);
int time = random.Next(0, Consts.DayHours + 1 - duration);
int pos = day * nr * Consts.DayHours + room * Consts.DayHours + time;
// fill time-space slots, for each hour of class
for (int i = duration - 1; i >= 0; i--)
newChromosome.Slots[pos + i].Add(courseClass);
// insert in class table of chromosome
newChromosome.Classes.Add(courseClass, pos);
}
newChromosome.CalculateFitness();
return newChromosome;
}
// Performes crossover operation using to chromosomes and returns pointer to offspring
public Schedule Crossover(Schedule parent2)
{
// // check probability of crossover operation
if (random.Next(100) > CrossoverProbability)
// no crossover, just copy first parent
return new Schedule(this, false);
// new chromosome object, copy chromosome setup
Schedule n = new Schedule(this, true);
//// number of classes
int size = Classes.Count;
List<bool> cp = new List<bool>(size);
for (int i = 0; i < size; ++i)
cp.Add(false);
// determine crossover point (randomly)
for (int i = NumberOfCrossoverPoints; i > 0; i--)
{
while (true)
{
int p = random.Next(size);
if (!cp[p])
{
cp[p] = true;
break;
}
}
}
// make new code by combining parent codes
bool first = random.Next(1000) % 2 == 0;
for (int i = 0, k = 0, j = 0; i < size; i++, j++, k++)
{
if (first)
{
// insert class from first parent into new chromosome's calss table
var classValue = Classes.ElementAt(k);
n.Classes.Add(classValue.Key, classValue.Value);
// all time-space slots of class are copied
for (int x = classValue.Key.LessonDuration - 1; x >= 0; x--)
{
n.Slots[classValue.Value + x].Add(classValue.Key);
}
}
else
{
// insert class from second parent into new chromosome's calss table
var classValue = parent2.Classes.ElementAt(j);
n.Classes.Add(classValue.Key, classValue.Value);
// all time-space slots of class are copied
for (int x = classValue.Key.LessonDuration - 1; x >= 0; x--)
{
n.Slots[classValue.Value + x].Add(classValue.Key);
}
}
//crossover point
if (cp[i])
first = !first;
}
n.CalculateFitness();
return n;
}