private void Initialize(int swarmSize, Function func)
{
Func = func;
Swarm.Particles.Clear();
for (int i = 0; i < swarmSize; i++)
{
var particle = new Particle();
particle.Generate(Func, Random);
Swarm.Particles.Add(particle);
if (particle.Fp < Swarm.Fg)
{
Swarm.UpdateG(particle.P, Func);
}
}
}
public void Run(int swarmSize, Function func)
{
var watch = System.Diagnostics.Stopwatch.StartNew();
Initialize(swarmSize, func);
double vMax = Math.Abs(Func.BoundUpper - Func.BoundLower) * .1;
const double wLow = 0.1;
var best = new Particle();
int lastImprovementOn = 0;
for (int iter = 0; iter < func.IterationsNumber; iter++)
{
double w = func.MaxVelocity - (func.MaxVelocity - wLow) * iter / func.IterationsNumber;
foreach (Particle particle in Swarm.Particles)
{
for (int d = 0; d < Func.Dimensions; d++)
{
double rp = Random.NextDouble();
double rg = Random.NextDouble();
particle.V[d] = w * particle.V[d] + PhiP * rp * (particle.P[d] - particle.X[d]) +
PhiG * rg * (Swarm.G[d] - particle.X[d]);
particle.V[d] = Math.Min(particle.V[d], vMax);
particle.V[d] = Math.Max(particle.V[d], -vMax);
particle.X[d] += particle.V[d];
particle.X[d] = Math.Max(particle.X[d], Func.BoundLower);
particle.X[d] = Math.Min(particle.X[d], Func.BoundUpper);
}
particle.Fx = Func.F(particle.X);
if (particle.Fx < particle.Fp)
{
particle.UpdateP();
}
else if (Random.NextDouble() <= func.KillProbability)
{
particle.Generate(func, Random);
}
if (particle.Fp < Swarm.Fg)
{
Swarm.UpdateG(particle.P, Func);
lastImprovementOn = iter;
best = particle;
}
}
Console.WriteLine($"#{iter,-4} Best G = {Swarm.Fg,-16:0.000000000000} W = {w,-7:0.00000}");
}
watch.Stop();
Console.WriteLine($"\nLast improvement was on iteration #{lastImprovementOn}. Time elapsed: {watch.Elapsed}");
Console.WriteLine("Coordinates of the best");
foreach (double x in best.X)
{
Console.Write($"{x,20}");
}
Console.WriteLine();
}
