public int[] FindIndicesOfFittestIndividuals(Array <Fitness> fitnesses)
{
if (fitnesses.ContainsNulls())
{
throw new ArgumentException(nameof(fitnesses));
}
if (fitnesses.Length < _fittestCount)
{
throw new ArgumentException(nameof(fitnesses));
}
var objectiveCount = fitnesses[0].Count;
for (int i = 0; i < fitnesses.Length; i++)
{
if (fitnesses[i].Count != objectiveCount)
{
throw new ArgumentException(nameof(fitnesses));
}
}
var dominatedByCounts = Pareto.ComputeDominatedByCounts(fitnesses);
var indices = new int[fitnesses.Length];
for (int i = 0; i < indices.Length; i++)
{
indices[i] = i;
}
var fronts = indices
.GroupBy(i => dominatedByCounts[i])
.OrderBy(g => g.Key)
.Select(g => g.ToList())
.ToList();
var fittestIndices = new List <int>(_fittestCount);
foreach (var front in fronts)
{
if (fittestIndices.Count + front.Count <= _fittestCount)
{
fittestIndices.AddRange(front);
}
else
{
var mostDiverse = OrderFrontByDiversity(front, fitnesses).Take(_fittestCount - (fittestIndices.Count));
fittestIndices.AddRange(mostDiverse);
break;
}
}
// Sanity check
if (fittestIndices.Count != _fittestCount)
{
throw new InvalidOperationException();
}
// Sanity check
if (fittestIndices.Distinct().Count() != fittestIndices.Count)
{
throw new InvalidOperationException();
}
// Sanity check
if (fittestIndices.Any(i => i < 0))
{
throw new InvalidOperationException();
}
return(fittestIndices.ToArray());
}
