public double EvaluateFitness(GAF.Chromosome chromosome)
{
double fitnessValue = -1;
if (chromosome != null)
{
//this is a range constant that is used to keep the x/y range between -100 and +100
var rangeConst = 200 / (System.Math.Pow(2, chromosome.Count / 2) - 1);
//get x and y from the solution
var x1 = Convert.ToInt32(chromosome.ToBinaryString(0, chromosome.Count / 2), 2);
var y1 = Convert.ToInt32(chromosome.ToBinaryString(chromosome.Count / 2, chromosome.Count / 2), 2);
//Adjust range to -100 to +100
var x = (x1 * rangeConst) - 100;
var y = (y1 * rangeConst) - 100;
//using binary F6 for fitness.
var temp1 = System.Math.Sin(System.Math.Sqrt(x * x + y * y));
var temp2 = 1 + 0.001 * (x * x + y * y);
var result = 0.5 + (temp1 * temp1 - 0.5) / (temp2 * temp2);
fitnessValue = 1 - result;
}
else
{
//chromosome is null
throw new ArgumentNullException("chromosome", "The specified Chromosome is null.");
}
return(fitnessValue);
}