/// <summary>
/// Judges 2 solutions by how many cowboys they have alive in them
/// </summary>
/// <param name="negSoln">The solution which if better elicits a -1 response</param>
/// <param name="posSoln">The solution which if better elicits a 1 response</param>
/// <returns>-1 if the negative solution is better, 1 if the positive solution is better, 0 if they are equal</returns>
public static int judgeByNumAlive(Solution negSoln, Solution posSoln)
{
//tell the problem we are making a comparison
posSoln.problem.compare();
//first check if they are null
if (posSoln == null && negSoln == null)
{
return 0;
}
else if (posSoln == null)
{
return -1;
}
else if (negSoln == null)
{
return 1;
}
else
{
//Here we want to select the one with the maximum number of living cowboys
int posAlive = posSoln.getNumAlive();
int negAlive = negSoln.getNumAlive();
if (posAlive > negAlive)
{
return 1;
}
else if (posAlive < negAlive)
{
return -1;
}
else //if posAlive == negAlive
{
return 0;
}
}
}
/// <summary>
/// Overrides the execute method in Problem, eliminates the worst performing cowboys and
/// breeds new ones using the visibility as a fitness function
/// </summary>
public override void execute()
{
Cowboy[] cowboys = solutions[solutions.Count - 1].Cowboys;
List<Cowboy> sortingList = new List<Cowboy>();
sortingList.AddRange(cowboys);
sortingList.Sort(Cowboy.sortByNumSeen);
sortingList.RemoveRange(NumCowboys / 2, NumCowboys / 2);
Cowboy[] remaining = sortingList.ToArray<Cowboy>();
while (sortingList.Count < NumCowboys)
{
sortingList.Add(breedNewCowboy(remaining));
}
solutions[0] = new Solution(this, sortingList.ToArray<Cowboy>());
}
/// <summary>
/// Breeds a new solution at random from a list of possible parents
/// </summary>
/// <param name="solutionsList">The list of potential parent</param>
/// <returns>A solution gotten by breeding 2 of the solutions on the list</returns>
public virtual Solution breedNewSolution(Solution[] solutionsList)
{
if (Random.Next(MutationChance) == 0)
{
return new Solution(this);
}
else
{
Solution s1 = solutionsList[rand.Next(solutionsList.Length - 1)];
Solution s2 = solutionsList[rand.Next(solutionsList.Length - 1)];
while (s1 == s2)
{
s2 = solutionsList[rand.Next(solutionsList.Length - 1)];
}
List<Cowboy> completeGenes = new List<Cowboy>();
for (int i = 0; i < NumCowboys; i++)
{
if (i % 2 == 0)
{
Cowboy c = s1.Cowboys[i];
completeGenes.Add(new Cowboy(this, new decimal[] { c.Location[0], c.Location[1] }));
}
else
{
Cowboy c = s2.Cowboys[i];
completeGenes.Add(new Cowboy(this, new decimal[] { c.Location[0], c.Location[1] }));
}
}
return new Solution(this, completeGenes.ToArray<Cowboy>());
}
}
/// <summary>
/// Judges 2 solutions their total visibility, with lower being better
/// </summary>
/// <param name="negSoln">The solution which if better elicits a -1 response</param>
/// <param name="posSoln">The solution which if better elicits a 1 response</param>
/// <returns>-1 if the negative solution is better, 1 if the positive solution is better, 0 if they are equal</returns>
public static int judgeByTotalVisibility(Solution negSoln, Solution posSoln)
{
posSoln.problem.compare();
if (posSoln == null && negSoln == null)
{
return 0;
}
else if (posSoln == null)
{
return -1;
}
else if (negSoln == null)
{
return 1;
}
else
{
//In this case we want the lowest value for the number of cowboys that can
//see each other.
int numSeenPos = posSoln.getVisibility();
int numSeenNeg = negSoln.getVisibility();
if (numSeenPos > numSeenNeg)
{
return -1;
}
else if (numSeenPos < numSeenNeg)
{
return 1;
}
else //If numSeenPos == numSeenNeg
{
return 0;
}
}
}