public PsoOptimizer(double bestGlobalError, double[] bestGlobalPosition, Particle[] swarm,
PsoArguments psoArguments)
{
Arguments = psoArguments;
BestGlobalError = bestGlobalError;
Swarm = swarm;
BestGlobalPosition = bestGlobalPosition;
}
/// <summary>
/// Init PSO
/// </summary>
/// <returns></returns>
public static PsoOptimizer Build(int dimensions,
Func <double[], double> errorFunc,
PsoArguments psoArguments)
{
var swarm = Enumerable.Range(0, psoArguments.SwarmSize)
.Select(i => new Particle(dimensions, errorFunc, psoArguments))
.ToArray();
var bestGlobalError = swarm[0].Objective;
var bestGlobalPosition = new double[dimensions];
swarm[0].Position.CopyTo(bestGlobalPosition, 0);
var particleIndex = Enumerable.Range(0, swarm.Length).ToArray();
// Update Ring Inline (Define which particle Learning from)
for (var i = 0; i < particleIndex.Length; i++)
{
var informers = new List <Particle>();
var numberOfinformers = psoArguments.MaxInformers / 2;
for (var n = 1; n <= numberOfinformers; n++)
{
var p = i - n;
while (p < 0)
{
p = swarm.Length + p;
}
informers.Add(swarm[particleIndex[p]]);
}
numberOfinformers += psoArguments.MaxInformers % 2;
for (var n = 1; n <= numberOfinformers; n++)
{
var p = i + n;
while (p >= swarm.Length)
{
p = p - swarm.Length;
}
informers.Add(swarm[particleIndex[p]]);
}
swarm[particleIndex[i]].InformersList = informers;
}
return(new PsoOptimizer(bestGlobalError, bestGlobalPosition, swarm, psoArguments));
}
/// <summary>
///
/// </summary>
/// <param name="dimensions"></param>
/// <param name="errorFunc"></param>
public Particle(int dimensions, Func <double[], double> errorFunc, PsoArguments arguments)
{
Random = new Random();
Dimensions = dimensions;
Arguments = arguments;
ErrorFunc = errorFunc;
InformersList = new List <Particle>();
Velocity = Enumerable.Range(0, Dimensions)
.Select(i => Random.NextDouble(Arguments.RangeMin, Arguments.RangeMax)).ToArray();
Position = Enumerable.Range(0, Dimensions)
.Select(i => Random.NextDouble(Arguments.RangeMin, Arguments.RangeMax)).ToArray();
BestPosition = new double[Dimensions];
Position.CopyTo(BestPosition, 0);
Objective = ErrorFunc(Position);
BestError = Objective;
}
