protected override double GetSwapImprovement(int i, int j)
{
var original = GetCost();
var originalSolution = Solution.ToList();
var swapper = new SwapOp {
Index1 = i, Index2 = j
};
swapper.Swap(Solution);
var newCost = GetCost();
Solution = originalSolution.ToArray();
return(original - newCost);
}
public void Update()
{
var gBest = _particles.MinBy(a => _calculatePerformance(a.BestPosition)).BestPosition.ToList();
Solution = gBest.ToArray();
Cost = _calculatePerformance(Solution);
Parallel.ForEach(_particles, particle =>
//foreach (var particle in _particles)
{
var myGbestList = gBest.ToList();
var tempVelocities = new List <SwapOp>();
for (var i = 0; i < _solutionLength; i++)
{
if (particle.Position[i] != particle.BestPosition[i])
{
var swap = new SwapOp
{
Probability = Alpha,
Index1 = i,
Index2 = particle.BestPosition.ToList().IndexOf(particle.Position[i])
};
if (swap.Index2 == -1)
{
var x = 0;
}
tempVelocities.Add(swap);
swap.Swap(particle.BestPosition);
}
if (particle.Position[i] != myGbestList[i])
{
var swap = new SwapOp
{
Probability = Beta,
Index1 = i,
Index2 = myGbestList.IndexOf(particle.Position[i])
};
if (swap.Index2 == -1)
{
var x = 0;
}
tempVelocities.Add(swap);
swap.Swap(particle.BestPosition);
}
}
foreach (var tempVelocity in tempVelocities)
{
if (Program.GetRN() < tempVelocity.Probability)
{
tempVelocity.Swap(particle.Position);
}
}
var cost = _calculatePerformance(particle.Position);
var bestCost = _calculatePerformance(particle.BestPosition);
if (cost < bestCost)
{
particle.Position.CopyTo(particle.BestPosition, 0);
}
});
}