public bool Add(Individual_NSGA individual)
{
if (individualList.Count == population_size)
{
return(false);
}
individualList.Add(individual);
return(true);
}
//tinh mse cho moi ca the
//private double CalculateMSE(Individual_NSGA individual, double[][] inputData)
//{
// // Chỗ này chính là chỗ cần dùng với RBF đây
// RadialNetwork rn = new RadialNetwork(m_RadialNetwork);
// double fitness = 0.0;
// rn.SetWeights(individual.values);
// fitness = rn.Accuracy(inputData);
// return fitness;
//}
//tinh mse cho moi ca the
private double CalculateMSE(Individual_NSGA individual, double[][] inputData)
{
// Chỗ này chính là chỗ cần dùng với RBF đây
RadialNetwork rn = new RadialNetwork(m_RadialNetwork);
double fitness = 0.0;
rn.SetWeights(individual.values);
fitness = rn.getMSEOf(inputData);
return(fitness);
}
public void Population_init(int n_gens, int numberOfObjectives)
{
Random r = new Random();
Individual_NSGA individualItem;
for (int i = 0; i < population_size; i++)
{
individualItem = new Individual_NSGA(n_gens, numberOfObjectives);
individualItem.Individual_init(r);
IndividualList.Add(individualItem);
}
}
public Individual_NSGA(Individual_NSGA w)
{
this.n_gens = w.n_gens;
this.values = w.Values;
this.numberOfObjectives = w.numberOfObjectives;
this.Objective = new double[this.numberOfObjectives];
for (int i = 0; i < this.Objective.Length; i++)
{
this.Objective[i] = w.Objective[i];
}
this.CrowdingDistance = w.CrowdingDistance;
this.OverallConstraintViolation = w.OverallConstraintViolation;
}
private void DoMutation(Individual_NSGA individual)
{
double rnd, delta1, delta2, mut_pow, deltaq;
double y, yl, yu, val, xy;
Individual_NSGA x = new Individual_NSGA(individual);
for (int var = 0; var < individual.N_gens; var++)
{
if (m_Random.NextDouble() <= mutationProb)
{
y = x.Values[var];
yl = x.GetLowerBound();
yu = x.GetUpperBound();
delta1 = (y - yl) / (yu - yl);
delta2 = (yu - y) / (yu - yl);
rnd = m_Random.NextDouble();
mut_pow = 1.0 / (eta_m + 1.0);
if (rnd <= 0.5)
{
xy = 1.0 - delta1;
val = 2.0 * rnd + (1.0 - 2.0 * rnd) * (Math.Pow(xy, (distributionIndex + 1.0)));
deltaq = Math.Pow(val, mut_pow) - 1.0;
}
else
{
xy = 1.0 - delta2;
val = 2.0 * (1.0 - rnd) + 2.0 * (rnd - 0.5) * (Math.Pow(xy, (distributionIndex + 1.0)));
deltaq = 1.0 - (Math.Pow(val, mut_pow));
}
y = y + deltaq * (yu - yl);
if (y < yl)
{
y = yl;
}
if (y > yu)
{
y = yu;
}
x.Values[var] = y;
//x.SetValue(var, y);
}
}
}
/// <summary>
/// Runs the NSGA-II algorithm.
/// </summary>
/// <returns>a <code>SolutionSet</code> that is a set of non dominated solutions as a result of the algorithm execution</returns>
public Population_NSGA Execute()
{
int evaluations;
Population_NSGA population;
Population_NSGA offspringPopulation;
Population_NSGA union;
//Initialize the variables
evaluations = 0;
// Bước 1: Khởi tạo quần thể
// Create the initial solutionSet
population = new Population_NSGA(m_Population_size);
population = (Population_NSGA)Population.Clone();
// Danh gia ham muc tieu 1 cho quan the Pt
for (int i = 0; i < m_Population_size; i++)
{
Individual_NSGA individual = population.IndividualList[i];
individual.Objective[0] = CalculateMSE(individual, inputData);
}
// Danh gia ham muc tieu 2 cho quan the Pt
Diversity(population);
// Vòng lặp tiến hóa
while (evaluations < m_MaxEvaluations)
{
// Create the offSpring solutionSet
offspringPopulation = new Population_NSGA(m_Population_size); // Tập cá thể con
Individual_NSGA[] parents = new Individual_NSGA[2];
for (int i = 0; i < (m_Population_size / 2); i++) // N/2
{
if (evaluations < m_MaxEvaluations)
{
//Lấy 2 Cha parents
int sol1 = (int)(m_Random.NextDouble() * (m_Population_size - 1));
int sol2 = (int)(m_Random.NextDouble() * (m_Population_size - 1));
parents[0] = population.IndividualList[sol1];
parents[1] = population.IndividualList[sol2];
//
while (sol1 == sol2)
{
sol2 = (int)(m_Random.NextDouble() * (m_Population_size - 1));
parents[1] = population.IndividualList[sol2];
}
// Sử dụng SBX crossover tạo ra 2 thằng con
Individual_NSGA[] offSpring = SBXCrossover(parents);
//Dot bien
DoMutation(offSpring[0]);
DoMutation(offSpring[1]);
//Danh gia ham muc tieu 1 cho quan the moi Qt
offSpring[0].Objective[0] = CalculateMSE(offSpring[0], inputData);
offSpring[1].Objective[0] = CalculateMSE(offSpring[1], inputData);
// Đưa 2 con vào danh sách
offspringPopulation.Add(offSpring[0]);
offspringPopulation.Add(offSpring[1]);
evaluations += 2;
}
}
//Danh gia ham muc tieu 2 cho quan the moi Qt
Diversity(offspringPopulation);
// Create the solutionSet union of solutionSet and offSpring
union = ((Population_NSGA)population).Union(offspringPopulation);
// Ranking the union - Sxep ko troi - non-dominated sorting
Ranking ranking = new Ranking(union);
int remain = m_Population_size;
int index = 0;
Population_NSGA front = null;
population.Clear();
// Obtain the next front
front = ranking.GetSubfront(index);
// Đưa các Front vào quần thể mới, đến thằng cuối cùng
while ((remain > 0) && (remain >= front.Size()))
{
//Assign crowding distance to individuals
// Gắn khoang cach CrowdingDistance cho ca the
CrowdingDistanceAssignment(front);
//Add the individuals of this front
for (int k = 0; k < front.Size(); k++)
{
population.Add(front.Get(k));
}
//Decrement remain
remain = remain - front.Size();
//Obtain the next front
index++;
if (remain > 0)
{
front = ranking.GetSubfront(index);
}
}
// Remain is less than front(index).size, insert only the best one
if (remain > 0)
{ // front contains individuals to insert
CrowdingDistanceAssignment(front);
front.Sort(new CrowdingComparator());
for (int k = 0; k < remain; k++)
{
population.Add(front.Get(k));
}
remain = 0;
}
}
// Return the first non-dominated front
Ranking rank = new Ranking(population);
Population_NSGA result = rank.GetSubfront(0);
return(result);
}
private Individual_NSGA[] DoCrossover(double crossoverProbability, Individual_NSGA parent1, Individual_NSGA parent2)
{
Individual_NSGA[] offSpring = new Individual_NSGA[2];
offSpring[0] = new Individual_NSGA(parent1);
offSpring[1] = new Individual_NSGA(parent2);
int i;
double rand;
double y1, y2, yL, yu;
double c1, c2;
double alpha, beta, betaq;
double valueX1, valueX2;
Individual_NSGA x1 = new Individual_NSGA(parent1);
Individual_NSGA x2 = new Individual_NSGA(parent2);
Individual_NSGA offs1 = new Individual_NSGA(offSpring[0]);
Individual_NSGA offs2 = new Individual_NSGA(offSpring[1]);
int numberOfVariables = x1.N_gens;
if (m_Random.NextDouble() <= crossoverProbability)
{
for (i = 0; i < numberOfVariables; i++)
{
valueX1 = x1.Values[i];
valueX2 = x2.Values[i];
if (m_Random.NextDouble() <= 0.5)
{
if (Math.Abs(valueX1 - valueX2) > EPS)
{
if (valueX1 < valueX2)
{
y1 = valueX1;
y2 = valueX2;
}
else
{
y1 = valueX2;
y2 = valueX1;
}
yL = x1.GetLowerBound(); //lowerBound
yu = x1.GetUpperBound(); //upperBound
rand = m_Random.NextDouble();
beta = 1.0 + (2.0 * (y1 - yL) / (y2 - y1));
alpha = 2.0 - Math.Pow(beta, -(distributionIndex + 1.0));
if (rand <= (1.0 / alpha))
{
betaq = Math.Pow((rand * alpha), (1.0 / (distributionIndex + 1.0)));
}
else
{
betaq = Math.Pow((1.0 / (2.0 - rand * alpha)), (1.0 / (distributionIndex + 1.0)));
}
c1 = 0.5 * ((y1 + y2) - betaq * (y2 - y1));
beta = 1.0 + (2.0 * (yu - y2) / (y2 - y1));
alpha = 2.0 - Math.Pow(beta, -(distributionIndex + 1.0));
if (rand <= (1.0 / alpha))
{
betaq = Math.Pow((rand * alpha), (1.0 / (distributionIndex + 1.0)));
}
else
{
betaq = Math.Pow((1.0 / (2.0 - rand * alpha)), (1.0 / (distributionIndex + 1.0)));
}
c2 = 0.5 * ((y1 + y2) + betaq * (y2 - y1));
if (c1 < yL)
{
c1 = yL;
}
if (c2 < yL)
{
c2 = yL;
}
if (c1 > yu)
{
c1 = yu;
}
if (c2 > yu)
{
c2 = yu;
}
if (m_Random.NextDouble() <= 0.5)
{
offs1.Values[i] = c2;
offs2.Values[i] = c1;
//offs1.SetValue(i, c2);
//offs2.SetValue(i, c1);
}
else
{
offs1.Values[i] = c1;
offs2.Values[i] = c2;
//offs1.SetValue(i, c1);
//offs2.SetValue(i, c2);
}
}
else
{
offs1.Values[i] = valueX1;
offs2.Values[i] = valueX2;
//offs1.SetValue(i, valueX1);
//offs2.SetValue(i, valueX2);
}
}
else
{
offs1.Values[i] = valueX2;
offs2.Values[i] = valueX1;
//offs1.SetValue(i, valueX2);
//offs2.SetValue(i, valueX1);
}
}
}
return(offSpring);
}
