internal double Decay(double drate, double rem)
{
//defines the sorting order for the species members
Comparison <Int32> comp = delegate(int x, int y)
{
Organism <T> m1 = pop.GetMember(x);
Organism <T> m2 = pop.GetMember(y);
return(m1.CompareTo(m2));
};
//sorts the members by fitness
members.Sort(comp);
////determins the number of creatures left alive
//int nalive = (int)Math.Floor(drate * members.Count);
//nalive = members.Count - (nalive + 1);
//if (nalive < 1) nalive = 1;
//determins the number of creatures that should die
double dead = drate * members.Count;
int ndead = (int)dead.Floor();
rem = rem + dead.Frac();
//updates the count if the remainder is more than one
if (rem >= 1.0)
{
ndead = ndead + 1;
rem = rem - 1.0;
}
//uses the dead count to determin how many are left alive
int nalive = members.Count - ndead;
//removes the members whose fitness is too low
for (int i = members.Count - 1; i >= nalive; i--)
{
int index = members[i];
pop.MarkForDeath(index);
members.RemoveAt(i);
}
return(rem);
}