/// <summary>
        /// Executes the operation
        /// </summary>
        /// <param name="obj">An object containing the population and the position (index) of the current individual</param>
        /// <returns>An object containing the three selected parents</returns>
        public override object Execute(object obj)
        {
            object[]    parameters = (object[])obj;
            SolutionSet population = (SolutionSet)parameters[0];
            int         index      = (int)parameters[1];

            Solution[] parents = new Solution[3];
            int        r1, r2, r3;

            if (population.Size() < 4)
            {
                throw new Exception("DifferentialEvolutionSelection: the population has less than four solutions");
            }

            do
            {
                r1 = (int)(JMetalRandom.Next(0, population.Size() - 1));
            } while (r1 == index);
            do
            {
                r2 = (int)(JMetalRandom.Next(0, population.Size() - 1));
            } while (r2 == index || r2 == r1);
            do
            {
                r3 = (int)(JMetalRandom.Next(0, population.Size() - 1));
            } while (r3 == index || r3 == r1 || r3 == r2);

            parents[0] = population.Get(r1);
            parents[1] = population.Get(r2);
            parents[2] = population.Get(r3);

            return(parents);
        }
        /// <summary>
        /// Returns a permutation vector between the 0 and (length - 1)
        /// </summary>
        /// <param name="length"></param>
        /// <returns></returns>
        public int[] IntPermutation(int length)
        {
            int[] aux    = new int[length];
            int[] result = new int[length];

            // First, create an array from 0 to length - 1.
            // Also is needed to create an random array of size length
            for (int i = 0; i < length; i++)
            {
                result[i] = i;
                aux[i]    = JMetalRandom.Next(0, length - 1);
            }

            // Sort the random array with effect in result, and then we obtain a
            // permutation array between 0 and length - 1
            for (int i = 0; i < length; i++)
            {
                for (int j = i + 1; j < length; j++)
                {
                    if (aux[i] > aux[j])
                    {
                        int tmp;
                        tmp       = aux[i];
                        aux[i]    = aux[j];
                        aux[j]    = tmp;
                        tmp       = result[i];
                        result[i] = result[j];
                        result[j] = tmp;
                    }
                }
            }

            return(result);
        }
        public override Solution GetOffspring(SolutionSet solutionSet, int index)
        {
            Solution[] parents   = new Solution[3];
            Solution   offSpring = null;

            try
            {
                int r1, r2;
                do
                {
                    r1 = JMetalRandom.Next(0, solutionSet.Size() - 1);
                } while (r1 == index);
                do
                {
                    r2 = JMetalRandom.Next(0, solutionSet.Size() - 1);
                } while (r2 == index || r2 == r1);

                parents[0] = solutionSet.Get(r1);
                parents[1] = solutionSet.Get(r2);
                parents[2] = solutionSet.Get(index);

                offSpring = (Solution)crossover.Execute(new object[] { solutionSet.Get(index), parents });
            }
            catch (Exception ex)
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".GetOffSpring()", ex);
                Console.Error.WriteLine("Exception in " + this.GetType().FullName + ".GetOffSpring()");
            }

            //Create a new solution, using DE
            return(offSpring);
        }
Example #4
0
        /// <summary>
        ///
        /// </summary>
        /// <param name="list">the set of the indexes of selected mating parents</param>
        /// <param name="cid">the id of current subproblem</param>
        /// <param name="size">the number of selected mating parents</param>
        /// <param name="type">1 - neighborhood; otherwise - whole population</param>
        private void MatingSelection(List <int> list, int cid, int size, int type)
        {
            int ss;
            int r;
            int p;

            ss = neighborhood[cid].Length;
            while (list.Count < size)
            {
                if (type == 1)
                {
                    r = JMetalRandom.Next(0, ss - 1);
                    p = neighborhood[cid][r];
                }
                else
                {
                    p = JMetalRandom.Next(0, populationSize - 1);
                }
                bool flag = true;
                for (int i = 0; i < list.Count; i++)
                {
                    if (list[i] == p)                     // p is in the list
                    {
                        flag = false;
                        break;
                    }
                }

                if (flag)
                {
                    list.Add(p);
                }
            }
        }
Example #5
0
        /// <summary>
        /// Performs the operation
        /// </summary>
        /// <param name="obj">Object representing a SolutionSet. This solution set must be an instancen <code>AdaptiveGridArchive</code></param>
        /// <returns>the selected solution</returns>
        public override object Execute(object obj)
        {
            try
            {
                AdaptiveGridArchive archive = (AdaptiveGridArchive)obj;
                int selected;
                int hypercube1 = archive.Grid.RandomOccupiedHypercube();
                int hypercube2 = archive.Grid.RandomOccupiedHypercube();

                if (hypercube1 != hypercube2)
                {
                    if (archive.Grid.GetLocationDensity(hypercube1) < archive.Grid.GetLocationDensity(hypercube2))
                    {
                        selected = hypercube1;
                    }
                    else if (archive.Grid.GetLocationDensity(hypercube2) <
                             archive.Grid.GetLocationDensity(hypercube1))
                    {
                        selected = hypercube2;
                    }
                    else
                    {
                        if (JMetalRandom.NextDouble() < 0.5)
                        {
                            selected = hypercube2;
                        }
                        else
                        {
                            selected = hypercube1;
                        }
                    }
                }
                else
                {
                    selected = hypercube1;
                }
                int bas = JMetalRandom.Next(0, archive.Size() - 1);
                int cnt = 0;
                while (cnt < archive.Size())
                {
                    Solution individual = archive.Get((bas + cnt) % archive.Size());
                    if (archive.Grid.Location(individual) != selected)
                    {
                        cnt++;
                    }
                    else
                    {
                        return(individual);
                    }
                }
                return(archive.Get((bas + cnt) % archive.Size()));
            }
            catch (InvalidCastException ex)
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".Execute()", ex);
                throw new Exception("Exception in " + this.GetType().FullName + ".Execute()");
            }
        }
Example #6
0
        /// <summary>
        ///
        /// </summary>
        /// <param name="cid">the id of current subproblem</param>
        /// <param name="type">1 - neighborhood; otherwise - whole  population</param>
        public int ACOrSelection3(int cid, int type)
        {
            int ss;

            ss = neighborhood[cid].Length;
            double r;
            int    p = neighborhood[cid][0];

            Solution[] parents    = new Solution[ss];
            Solution[] parent     = new Solution[populationSize];
            double[]   fitness    = new double[ss];
            double[]   fit        = new double[populationSize];
            int        indexOfmin = 0;
            double     sum        = 0;

            double[] pro = new double[populationSize];
            double   a1  = 0;
            double   a2  = 0;

            if (type == 1)
            {
                indexOfmin = JMetalRandom.Next(0, ss - 1);
                p          = neighborhood[cid][indexOfmin];
            }
            else
            {
                for (int i = 0; i < populationSize; i++)
                {
                    parent[i] = population.Get(i);
                    fit[i]    = 1 / FitnessFunction(parent[i], lambda[cid]);
                    sum       = sum + fit[i];
                }
                for (int j = 0; j < populationSize; j++)
                {
                    pro[j] = fit[j] / sum;
                }
                r = JMetalRandom.NextDouble();
                for (int k = 0; k < pro.Length; k++)
                {
                    a2 = a2 + pro[k];
                    if (r < a2 && r >= a1)
                    {
                        p = k;
                        break;
                    }
                    a1 = a1 + pro[k];
                }
            }

            return(p);
        }
Example #7
0
        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="size">The size of the array</param>
        /// <param name="lowerBounds">Lower bounds</param>
        /// <param name="upperBounds">Upper bounds</param>
        public ArrayInt(int size, double[] lowerBounds, double[] upperBounds)
        {
            Size       = size;
            Array      = new int[Size];
            LowerBound = new int[Size];
            UpperBound = new int[Size];

            for (int i = 0; i < Size; i++)
            {
                LowerBound[i] = (int)lowerBounds[i];
                UpperBound[i] = (int)upperBounds[i];
                Array[i]      = JMetalRandom.Next(LowerBound[i], UpperBound[i]);
            }
        }
Example #8
0
        /// <summary>
        /// /Update the speed of each particle
        /// </summary>
        /// <param name="iter"></param>
        /// <param name="miter"></param>
        private void ComputeSpeed(int iter, int miter)
        {
            double r1, r2, W, C1, C2;
            double wmax, wmin;
            XReal  bestGlobal;

            for (int i = 0; i < swarmSize; i++)
            {
                XReal particle     = new XReal(particles.Get(i));
                XReal bestParticle = new XReal(best[i]);

                //Select a global best for calculate the speed of particle i, bestGlobal

                Solution one, two;
                int      pos1 = JMetalRandom.Next(0, Leaders.Size() - 1);
                int      pos2 = JMetalRandom.Next(0, Leaders.Size() - 1);
                one = Leaders.Get(pos1);
                two = Leaders.Get(pos2);

                if (crowdingDistanceComparator.Compare(one, two) < 1)
                {
                    bestGlobal = new XReal(one);
                }
                else
                {
                    bestGlobal = new XReal(two);
                    //Params for velocity equation
                }

                r1 = JMetalRandom.NextDouble(r1Min, r1Max);
                r2 = JMetalRandom.NextDouble(r2Min, r2Max);
                C1 = JMetalRandom.NextDouble(C1Min, C1Max);
                C2 = JMetalRandom.NextDouble(C2Min, C2Max);
                W  = JMetalRandom.NextDouble(WMin, WMax);

                wmax = WMax;
                wmin = WMin;

                for (int var = 0; var < particle.GetNumberOfDecisionVariables(); var++)
                {
                    //Computing the velocity of this particle
                    speed[i][var] = VelocityConstriction(ConstrictionCoefficient(C1, C2) * (InertiaWeight(iter, miter, wmax, wmin) * speed[i][var] + C1 * r1 * (bestParticle.GetValue(var) - particle.GetValue(var)) + C2 * r2 * (bestGlobal.GetValue(var) - particle.GetValue(var))),
                                                         deltaMax,
                                                         deltaMin,
                                                         var,
                                                         i);
                }
            }
        }
Example #9
0
        /// <summary>
        /// Constructor
        /// </summary>
        /// <param name="size">Size of the array</param>
        public ArrayInt(int size, Problem problem)
        {
            _problem   = problem;
            Size       = size;
            Array      = new int[size];
            LowerBound = new int[size];
            UpperBound = new int[size];

            for (int i = 0; i < Size; i++)
            {
                LowerBound[i] = (int)_problem.LowerLimit[i];
                UpperBound[i] = (int)_problem.UpperLimit[i];
                Array[i]      = JMetalRandom.Next(LowerBound[i], UpperBound[i]);
            }
        }
        /// <summary>
        /// Returns a <code>Solution</code> using the diversification generation method
        /// described in the scatter search template.
        /// </summary>
        /// <returns></returns>
        public Solution DiversificationGeneration()
        {
            Solution solution;

            solution = new Solution(this.Problem);
            XReal wrapperSolution = new XReal(solution);

            double value;
            int    range;

            for (int i = 0; i < this.Problem.NumberOfVariables; i++)
            {
                sumOfReverseFrequencyValues[i] = 0;
                for (int j = 0; j < numberOfSubranges; j++)
                {
                    reverseFrequency[j][i]          = sumOfFrequencyValues[i] - frequency[j][i];
                    sumOfReverseFrequencyValues[i] += reverseFrequency[j][i];
                }

                if (sumOfReverseFrequencyValues[i] == 0)
                {
                    range = JMetalRandom.Next(0, numberOfSubranges - 1);
                }
                else
                {
                    value = JMetalRandom.Next(0, sumOfReverseFrequencyValues[i] - 1);
                    range = 0;
                    while (value > reverseFrequency[range][i])
                    {
                        value -= reverseFrequency[range][i];
                        range++;
                    }
                }

                frequency[range][i]++;
                sumOfFrequencyValues[i]++;

                double low = this.Problem.LowerLimit[i] + range * (this.Problem.UpperLimit[i] -
                                                                   this.Problem.LowerLimit[i]) / numberOfSubranges;
                double high = low + (this.Problem.UpperLimit[i] -
                                     this.Problem.LowerLimit[i]) / numberOfSubranges;
                value = JMetalRandom.NextDouble(low, high);

                wrapperSolution.SetValue(i, value);
            }
            return(solution);
        }
Example #11
0
        /// <summary>
        /// Perform the mutation operation
        /// </summary>
        /// <param name="probability">Mutation probability</param>
        /// <param name="solution">The solution to mutate</param>
        private void DoMutation(double probability, Solution solution)
        {
            XReal v = new XReal(solution);

            try
            {
                if ((solution.Type.GetType() == typeof(BinarySolutionType)) ||
                    (solution.Type.GetType() == typeof(BinaryRealSolutionType)))
                {
                    for (int i = 0; i < solution.Variable.Length; i++)
                    {
                        for (int j = 0; j < ((Binary)solution.Variable[i]).NumberOfBits; j++)
                        {
                            if (JMetalRandom.NextDouble() < probability)
                            {
                                ((Binary)solution.Variable[i]).Bits.Flip(j);
                            }
                        }
                    }

                    for (int i = 0; i < solution.Variable.Length; i++)
                    {
                        ((Binary)solution.Variable[i]).Decode();
                    }
                }
                else
                {                 // Integer representation
                    for (int i = 0; i < solution.Variable.Length; i++)
                    {
                        if (JMetalRandom.NextDouble() < probability)
                        {
                            int value = JMetalRandom.Next(
                                (int)v.GetLowerBound(i),
                                (int)v.GetUpperBound(i));
                            v.SetValue(i, value);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                Logger.Log.Error("Error in " + this.GetType().FullName + ".DoMutation()", ex);
                Console.WriteLine("Error in " + this.GetType().FullName + ".DoMutation()");
                throw new Exception("Exception in " + this.GetType().FullName + ".DoMutation()");
            }
        }
Example #12
0
        /// <summary>
        /// Performs the operation
        /// </summary>
        /// <param name="obj">Object representing a SolutionSet.</param>
        /// <returns>An object representing an array with the selected parents</returns>
        public override object Execute(object obj)
        {
            SolutionSet population = (SolutionSet)obj;
            int         pos1, pos2;

            pos1 = JMetalRandom.Next(0, population.Size() - 1);
            pos2 = JMetalRandom.Next(0, population.Size() - 1);
            while ((pos1 == pos2) && (population.Size() > 1))
            {
                pos2 = JMetalRandom.Next(0, population.Size() - 1);
            }

            Solution[] parents = new Solution[2];
            parents[0] = population.Get(pos1);
            parents[1] = population.Get(pos2);

            return(parents);
        }
Example #13
0
        /// <summary>
        /// Performs the operation
        /// </summary>
        /// <param name="probability">Mutation probability</param>
        /// <param name="solution">The solution to mutate</param>
        private void DoMutation(double probability, Solution solution)
        {
            int[] permutation;
            int   permutationLength;

            if (solution.Type.GetType() == typeof(PermutationSolutionType))
            {
                permutationLength = ((Permutation)solution.Variable[0]).Size;
                permutation       = ((Permutation)solution.Variable[0]).Vector;

                if (JMetalRandom.NextDouble() < probability)
                {
                    int pos1;
                    int pos2;

                    pos1 = JMetalRandom.Next(0, permutationLength - 1);
                    pos2 = JMetalRandom.Next(0, permutationLength - 1);

                    while (pos1 == pos2)
                    {
                        if (pos1 == (permutationLength - 1))
                        {
                            pos2 = JMetalRandom.Next(0, permutationLength - 2);
                        }
                        else
                        {
                            pos2 = JMetalRandom.Next(pos1, permutationLength - 1);
                        }
                    }
                    // swap
                    int temp = permutation[pos1];
                    permutation[pos1] = permutation[pos2];
                    permutation[pos2] = temp;
                }
            }
            else
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".DoMutation()");
                Console.WriteLine("Exception in " + this.GetType().FullName + ".DoMutation()");
                throw new Exception("Exception in " + this.GetType().FullName + ".DoMutation()");
            }
        }
Example #14
0
        public static void RandomPermutation(int[] perm, int size)
        {
            int[]  index = new int[size];
            bool[] flag  = new bool[size];

            for (int n = 0; n < size; n++)
            {
                index[n] = n;
                flag[n]  = true;
            }

            int num = 0;

            while (num < size)
            {
                int start = JMetalRandom.Next(0, size - 1);

                while (true)
                {
                    if (flag[start])
                    {
                        perm[num]   = index[start];
                        flag[start] = false;
                        num++;
                        break;
                    }
                    if (start == (size - 1))
                    {
                        start = 0;
                    }
                    else
                    {
                        start++;
                    }
                }
            }
        }
Example #15
0
        /// <summary>
        /// Performs the operation
        /// </summary>
        /// <param name="obj">Object representing a SolutionSet</param>
        /// <returns>The selected solution</returns>
        public override object Execute(object obj)
        {
            SolutionSet solutionSet = (SolutionSet)obj;
            Solution    solution1, solution2;

            solution1 = solutionSet.Get(JMetalRandom.Next(0, solutionSet.Size() - 1));
            solution2 = solutionSet.Get(JMetalRandom.Next(0, solutionSet.Size() - 1));

            if (solutionSet.Size() >= 2)
            {
                while (solution1 == solution2)
                {
                    solution2 = solutionSet.Get(JMetalRandom.Next(0, solutionSet.Size() - 1));
                }
            }

            int flag = comparator.Compare(solution1, solution2);

            if (flag == -1)
            {
                return(solution1);
            }
            else if (flag == 1)
            {
                return(solution2);
            }
            else
            if (JMetalRandom.NextDouble() < 0.5)
            {
                return(solution1);
            }
            else
            {
                return(solution2);
            }
        }
        /// <summary>
        /// Executes the operation
        /// </summary>
        /// <param name="obj">An object containing an array of three parents</param>
        /// <returns>An object containing the offSprings</returns>
        public override object Execute(object obj)
        {
            object[] parameters = (object[])obj;
            Solution current    = (Solution)parameters[0];

            Solution[] parent = (Solution[])parameters[1];

            Solution child;

            if (!(VALID_TYPES.Contains(parent[0].Type.GetType()) &&
                  VALID_TYPES.Contains(parent[1].Type.GetType()) &&
                  VALID_TYPES.Contains(parent[2].Type.GetType())))
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".Execute()");
                throw new Exception("Exception in " + this.GetType().FullName + ".Execute()");
            }

            int jrand;

            child = new Solution(current);

            XReal xParent0 = new XReal(parent[0]);
            XReal xParent1 = new XReal(parent[1]);
            XReal xParent2 = new XReal(parent[2]);
            XReal xCurrent = new XReal(current);
            XReal xChild   = new XReal(child);

            int numberOfVariables = xParent0.GetNumberOfDecisionVariables();

            jrand = JMetalRandom.Next(0, numberOfVariables - 1);

            // STEP 4. Checking the DE variant
            if ((deVariant == "rand/1/bin") || (deVariant == "best/1/bin"))
            {
                for (int j = 0; j < numberOfVariables; j++)
                {
                    if (JMetalRandom.NextDouble(0, 1) < cr || j == jrand)
                    {
                        double value;
                        value = xParent2.GetValue(j) + f * (xParent0.GetValue(j) - xParent1.GetValue(j));

                        if (value < xChild.GetLowerBound(j))
                        {
                            value = xChild.GetLowerBound(j);
                        }
                        if (value > xChild.GetUpperBound(j))
                        {
                            value = xChild.GetUpperBound(j);
                        }

                        xChild.SetValue(j, value);
                    }
                    else
                    {
                        double value;
                        value = xCurrent.GetValue(j);
                        xChild.SetValue(j, value);
                    }
                }
            }
            else if ((deVariant == "rand/1/exp") || (deVariant == "best/1/exp"))
            {
                for (int j = 0; j < numberOfVariables; j++)
                {
                    if (JMetalRandom.NextDouble(0, 1) < cr || j == jrand)
                    {
                        double value;
                        value = xParent2.GetValue(j) + f * (xParent0.GetValue(j) - xParent1.GetValue(j));

                        if (value < xChild.GetLowerBound(j))
                        {
                            value = xChild.GetLowerBound(j);
                        }
                        if (value > xChild.GetUpperBound(j))
                        {
                            value = xChild.GetUpperBound(j);
                        }

                        xChild.SetValue(j, value);
                    }
                    else
                    {
                        cr = 0;
                        double value;
                        value = xCurrent.GetValue(j);
                        xChild.SetValue(j, value);
                    }
                }
            }
            else if ((deVariant == "current-to-rand/1") || (deVariant == "current-to-best/1"))
            {
                for (int j = 0; j < numberOfVariables; j++)
                {
                    double value;
                    value = xCurrent.GetValue(j) + k * (xParent2.GetValue(j)
                                                        - xCurrent.GetValue(j))
                            + f * (xParent0.GetValue(j) - xParent1.GetValue(j));

                    if (value < xChild.GetLowerBound(j))
                    {
                        value = xChild.GetLowerBound(j);
                    }
                    if (value > xChild.GetUpperBound(j))
                    {
                        value = xChild.GetUpperBound(j);
                    }

                    xChild.SetValue(j, value);
                }
            }
            else if ((deVariant == "current-to-rand/1/bin") || (deVariant == "current-to-best/1/bin"))
            {
                for (int j = 0; j < numberOfVariables; j++)
                {
                    if (JMetalRandom.NextDouble(0, 1) < cr || j == jrand)
                    {
                        double value;
                        value = xCurrent.GetValue(j) + k * (xParent2.GetValue(j)
                                                            - xCurrent.GetValue(j))
                                + f * (xParent0.GetValue(j) - xParent1.GetValue(j));

                        if (value < xChild.GetLowerBound(j))
                        {
                            value = xChild.GetLowerBound(j);
                        }
                        if (value > xChild.GetUpperBound(j))
                        {
                            value = xChild.GetUpperBound(j);
                        }

                        xChild.SetValue(j, value);
                    }
                    else
                    {
                        double value;
                        value = xCurrent.GetValue(j);
                        xChild.SetValue(j, value);
                    }
                }
            }
            else if ((deVariant == "current-to-rand/1/exp") || (deVariant == "current-to-best/1/exp"))
            {
                for (int j = 0; j < numberOfVariables; j++)
                {
                    if (JMetalRandom.NextDouble(0, 1) < cr || j == jrand)
                    {
                        double value;
                        value = xCurrent.GetValue(j) + k * (xParent2.GetValue(j)
                                                            - xCurrent.GetValue(j))
                                + f * (xParent0.GetValue(j) - xParent1.GetValue(j));

                        if (value < xChild.GetLowerBound(j))
                        {
                            value = xChild.GetLowerBound(j);
                        }
                        if (value > xChild.GetUpperBound(j))
                        {
                            value = xChild.GetUpperBound(j);
                        }

                        xChild.SetValue(j, value);
                    }
                    else
                    {
                        cr = 0.0;
                        double value;
                        value = xCurrent.GetValue(j);
                        xChild.SetValue(j, value);
                    }
                }
            }
            else
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".Execute()");
                throw new Exception("Exception in " + this.GetType().FullName + ".Execute()");
            }
            return(child);
        }
        /// <summary>
        /// Perform the crossover operation.
        /// </summary>
        /// <param name="probability">Crossover probability</param>
        /// <param name="parent1">The first parent</param>
        /// <param name="parent2">The second parent</param>
        /// <returns>An array containig the two offsprings</returns>
        private Solution[] DoCrossover(double probability, Solution parent1, Solution parent2)
        {
            Solution[] offSpring = new Solution[2];

            offSpring[0] = new Solution(parent1);
            offSpring[1] = new Solution(parent2);

            try
            {
                if (JMetalRandom.NextDouble() < probability)
                {
                    if ((parent1.Type.GetType() == typeof(BinarySolutionType)) ||
                        (parent1.Type.GetType() == typeof(BinaryRealSolutionType)))
                    {
                        //1. Compute the total number of bits
                        int totalNumberOfBits = 0;
                        for (int i = 0; i < parent1.Variable.Length; i++)
                        {
                            totalNumberOfBits += ((Binary)parent1.Variable[i]).NumberOfBits;
                        }

                        //2. Calculate the point to make the crossover
                        int crossoverPoint = JMetalRandom.Next(0, totalNumberOfBits - 1);

                        //3. Compute the encodings.variable containing the crossoverPoint bit
                        int variable   = 0;
                        int acountBits = ((Binary)parent1.Variable[variable]).NumberOfBits;

                        while (acountBits < (crossoverPoint + 1))
                        {
                            variable++;
                            acountBits += ((Binary)parent1.Variable[variable]).NumberOfBits;
                        }

                        //4. Compute the bit into the selected encodings.variable
                        int diff = acountBits - crossoverPoint;
                        int intoVariableCrossoverPoint = ((Binary)parent1.Variable[variable]).NumberOfBits - diff;

                        //5. Make the crossover into the gene;
                        Binary offSpring1, offSpring2;
                        offSpring1 = (Binary)parent1.Variable[variable].DeepCopy();
                        offSpring2 = (Binary)parent2.Variable[variable].DeepCopy();

                        for (int i = intoVariableCrossoverPoint; i < offSpring1.NumberOfBits; i++)
                        {
                            bool swap = offSpring1.Bits[i];
                            offSpring1.Bits[i] = offSpring2.Bits[i];
                            offSpring2.Bits[i] = swap;
                        }

                        offSpring[0].Variable[variable] = offSpring1;
                        offSpring[1].Variable[variable] = offSpring2;

                        //6. Apply the crossover to the other variables
                        for (int i = 0; i < variable; i++)
                        {
                            offSpring[0].Variable[i] = parent2.Variable[i].DeepCopy();

                            offSpring[1].Variable[i] = parent1.Variable[i].DeepCopy();
                        }

                        //7. Decode the results
                        for (int i = 0; i < offSpring[0].Variable.Length; i++)
                        {
                            ((Binary)offSpring[0].Variable[i]).Decode();
                            ((Binary)offSpring[1].Variable[i]).Decode();
                        }
                    }                     // Binary or BinaryReal
                    else
                    {                     // Integer representation
                        int crossoverPoint = JMetalRandom.Next(0, parent1.NumberOfVariables() - 1);
                        int valueX1;
                        int valueX2;
                        for (int i = crossoverPoint; i < parent1.NumberOfVariables(); i++)
                        {
                            valueX1 = ((Int)parent1.Variable[i]).Value;
                            valueX2 = ((Int)parent2.Variable[i]).Value;
                            ((Int)offSpring[0].Variable[i]).Value = valueX2;
                            ((Int)offSpring[1].Variable[i]).Value = valueX1;
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                Logger.Log.Error("Error in: " + this.GetType().FullName + ".DoCrossover()", ex);
                Console.WriteLine("Error in " + this.GetType().FullName + ".DoCrossover()");
                throw new Exception("Exception in " + this.GetType().FullName + ".DoCrossover()");
            }
            return(offSpring);
        }
Example #18
0
 /// <summary>
 /// Constructor
 /// </summary>
 /// <param name="lowerBound">Variable lower bound</param>
 /// <param name="upperBound">Variable upper bound</param>
 public Int(int lowerBound, int upperBound)
 {
     this.LowerBound = lowerBound;
     this.UpperBound = upperBound;
     this.Value      = JMetalRandom.Next(lowerBound, upperBound);
 }
        public override SolutionSet Execute()
        {
            double contrDE   = 0;
            double contrSBX  = 0;
            double contrBLXA = 0;
            double contrPol  = 0;

            double[] contrReal = new double[3];
            contrReal[0] = contrReal[1] = contrReal[2] = 0;

            IComparer <Solution> dominance          = new DominanceComparator();
            IComparer <Solution> crowdingComparator = new CrowdingComparator();
            Distance             distance           = new Distance();

            Operator selectionOperator;

            //Read parameter values
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "maxEvaluations", ref maxEvaluations);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "populationSize", ref populationSize);
            JMetalCSharp.Utils.Utils.GetIndicatorsFromParameters(this.InputParameters, "indicators", ref indicators);

            //Init the variables
            population  = new SolutionSet(populationSize);
            evaluations = 0;

            selectionOperator = Operators["selection"];

            Offspring[] getOffspring;
            int         N_O;     // number of offpring objects

            getOffspring = (Offspring[])GetInputParameter("offspringsCreators");
            N_O          = getOffspring.Length;

            contribution        = new double[N_O];
            contributionCounter = new int[N_O];

            contribution[0] = (double)(populationSize / (double)N_O) / (double)populationSize;
            for (int i = 1; i < N_O; i++)
            {
                contribution[i] = (double)(populationSize / (double)N_O) / (double)populationSize + (double)contribution[i - 1];
            }

            // Create the initial solutionSet
            Solution newSolution;

            for (int i = 0; i < populationSize; i++)
            {
                newSolution = new Solution(Problem);
                Problem.Evaluate(newSolution);
                Problem.EvaluateConstraints(newSolution);
                evaluations++;
                newSolution.Location = i;
                population.Add(newSolution);
            }

            while (evaluations < maxEvaluations)
            {
                // Create the offSpring solutionSet
                // Create the offSpring solutionSet
                offspringPopulation = new SolutionSet(2);
                Solution[] parents = new Solution[2];

                int      selectedSolution = JMetalRandom.Next(0, populationSize - 1);
                Solution individual       = new Solution(population.Get(selectedSolution));

                int      selected  = 0;
                bool     found     = false;
                Solution offSpring = null;
                double   rnd       = JMetalRandom.NextDouble();
                for (selected = 0; selected < N_O; selected++)
                {
                    if (!found && (rnd <= contribution[selected]))
                    {
                        if ("DE" == getOffspring[selected].Id)
                        {
                            offSpring = getOffspring[selected].GetOffspring(population, selectedSolution);
                            contrDE++;
                        }
                        else if ("SBXCrossover" == getOffspring[selected].Id)
                        {
                            offSpring = getOffspring[selected].GetOffspring(population);
                            contrSBX++;
                        }
                        else if ("BLXAlphaCrossover" == getOffspring[selected].Id)
                        {
                            offSpring = getOffspring[selected].GetOffspring(population);
                            contrBLXA++;
                        }
                        else if ("PolynomialMutation" == getOffspring[selected].Id)
                        {
                            offSpring = ((PolynomialMutationOffspring)getOffspring[selected]).GetOffspring(individual);
                            contrPol++;
                        }
                        else
                        {
                            Console.Error.WriteLine("Error in NSGAIIARandom. Operator " + offSpring + " does not exist");
                            Logger.Log.Error("NSGAIIARandom. Operator " + offSpring + " does not exist");
                        }

                        offSpring.Fitness = (int)selected;
                        currentCrossover  = selected;
                        found             = true;
                    }
                }

                Problem.Evaluate(offSpring);
                offspringPopulation.Add(offSpring);
                evaluations += 1;

                // Create the solutionSet union of solutionSet and offSpring
                union = ((SolutionSet)population).Union(offspringPopulation);

                // Ranking the union
                Ranking ranking = new Ranking(union);

                int         remain = populationSize;
                int         index  = 0;
                SolutionSet front  = null;
                population.Clear();

                // Obtain the next front
                front = ranking.GetSubfront(index);

                while ((remain > 0) && (remain >= front.Size()))
                {
                    //Assign crowding distance to individuals
                    distance.CrowdingDistanceAssignment(front, Problem.NumberOfObjectives);
                    //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
                    distance.CrowdingDistanceAssignment(front, Problem.NumberOfObjectives);
                    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);

            Result = rank.GetSubfront(0);

            return(Result);
        }
Example #20
0
        /// <summary>
        /// @author Juanjo This method selects N solutions from a set M, where N <= M
        /// using the same method proposed by Qingfu Zhang, W. Liu, and Hui Li in the
        /// paper describing MOEA/D-DRA (CEC 09 COMPTETITION) An example is giving in
        /// that paper for two objectives. If N = 100, then the best solutions
        /// attenting to the weights (0,1), (1/99,98/99), ...,(98/99,1/99), (1,0) are
        /// selected.
        ///
        /// Using this method result in 101 solutions instead of 100. We will just
        /// compute 100 even distributed weights and used them. The result is the
        /// same
        ///
        /// In case of more than two objectives the procedure is: 1- Select a
        /// solution at random 2- Select the solution from the population which have
        /// maximum distance to it (whithout considering the already included)
        /// </summary>
        /// <param name="n">The number of solutions to return</param>
        /// <returns>A solution set containing those elements</returns>
        private SolutionSet FinalSelection(int n)
        {
            SolutionSet res = new SolutionSet(n);

            if (Problem.NumberOfObjectives == 2)
            {             // subcase 1
                double[][] internLambda = new double[n][];
                for (int i = 0; i < n; i++)
                {
                    internLambda[i] = new double[2];
                }

                for (int i = 0; i < n; i++)
                {
                    double a = 1.0 * i / (n - 1);
                    internLambda[i][0] = a;
                    internLambda[i][1] = 1 - a;
                }

                // we have now the weights, now select the best solution for each of them
                for (int i = 0; i < n; i++)
                {
                    Solution currentBest = population.Get(0);
                    double   value       = FitnessFunction(currentBest, internLambda[i]);

                    for (int j = 1; j < n; j++)
                    {
                        double aux = FitnessFunction(population.Get(j), internLambda[i]); // we are looking the best for the weight i
                        if (aux < value)
                        {                                                                 // solution in position j is better!
                            value       = aux;
                            currentBest = population.Get(j);
                        }
                    }
                    res.Add(new Solution(currentBest));
                }
            }
            else
            {             // general case (more than two objectives)
                Distance distanceUtility = new Distance();
                int      randomIndex     = JMetalRandom.Next(0, population.Size() - 1);

                // create a list containing all the solutions but the selected one (only references to them)
                List <Solution> candidate = new List <Solution>();
                candidate.Add(population.Get(randomIndex));

                for (int i = 0; i < population.Size(); i++)
                {
                    if (i != randomIndex)
                    {
                        candidate.Add(population.Get(i));
                    }
                }

                while (res.Size() < n)
                {
                    int      index         = 0;
                    Solution selected      = candidate[0];                // it should be a next! (n <= population size!)
                    double   distanceValue = distanceUtility.DistanceToSolutionSetInObjectiveSpace(selected, res);
                    int      i             = 1;
                    while (i < candidate.Count)
                    {
                        Solution nextCandidate = candidate[i];
                        double   aux           = distanceValue = distanceUtility.DistanceToSolutionSetInObjectiveSpace(nextCandidate, res);
                        if (aux > distanceValue)
                        {
                            distanceValue = aux;
                            index         = i;
                        }
                        i++;
                    }

                    // add the selected to res and remove from candidate list
                    res.Add(new Solution(candidate[index]));
                    candidate.RemoveAt(index);
                }
            }
            return(res);
        }
Example #21
0
        /// <summary>
        /// Execute the algorithm
        /// </summary>
        /// <returns></returns>
        public override SolutionSet Execute()
        {
            int populationSize = -1,
                archiveSize    = -1,
                maxEvaluations = -1,
                evaluations    = -1,
                feedBack       = -1;

            Operator        mutationOperator, crossoverOperator, selectionOperator;
            SolutionSet     currentPopulation;
            CrowdingArchive archive;

            SolutionSet[]        neighbors;
            Neighborhood         neighborhood;
            IComparer <Solution> dominance          = new DominanceComparator();
            IComparer <Solution> crowdingComparator = new CrowdingComparator();
            Distance             distance           = new Distance();

            //Read the parameters
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "populationSize", ref populationSize);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "archiveSize", ref archiveSize);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "maxEvaluations", ref maxEvaluations);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "feedBack", ref feedBack);


            //Read the operators
            mutationOperator  = Operators["mutation"];
            crossoverOperator = Operators["crossover"];
            selectionOperator = Operators["selection"];

            //Initialize the variables
            //Initialize the population and the archive
            currentPopulation = new SolutionSet(populationSize);
            archive           = new CrowdingArchive(archiveSize, this.Problem.NumberOfObjectives);
            evaluations       = 0;
            neighborhood      = new Neighborhood(populationSize);
            neighbors         = new SolutionSet[populationSize];

            //Create the comparator for check dominance
            dominance = new DominanceComparator();

            //Create the initial population
            for (int i = 0; i < populationSize; i++)
            {
                Solution individual = new Solution(this.Problem);
                this.Problem.Evaluate(individual);
                this.Problem.EvaluateConstraints(individual);
                currentPopulation.Add(individual);
                individual.Location = i;
                evaluations++;
            }

            while (evaluations < maxEvaluations)
            {
                for (int ind = 0; ind < currentPopulation.Size(); ind++)
                {
                    Solution individual = new Solution(currentPopulation.Get(ind));

                    Solution[] parents = new Solution[2];
                    Solution[] offSpring;

                    neighbors[ind] = neighborhood.GetEightNeighbors(currentPopulation, ind);
                    neighbors[ind].Add(individual);

                    //parents
                    parents[0] = (Solution)selectionOperator.Execute(neighbors[ind]);
                    parents[1] = (Solution)selectionOperator.Execute(neighbors[ind]);

                    //Create a new individual, using genetic operators mutation and crossover
                    offSpring = (Solution[])crossoverOperator.Execute(parents);
                    mutationOperator.Execute(offSpring[0]);

                    //->Evaluate individual an his constraints
                    this.Problem.Evaluate(offSpring[0]);
                    this.Problem.EvaluateConstraints(offSpring[0]);
                    evaluations++;
                    //<-Individual evaluated

                    int flag = dominance.Compare(individual, offSpring[0]);

                    if (flag == 1)
                    {                     //The new individuals dominate
                        offSpring[0].Location = individual.Location;
                        currentPopulation.Replace(offSpring[0].Location, offSpring[0]);
                        archive.Add(new Solution(offSpring[0]));
                    }
                    else if (flag == 0)
                    {                    //The individuals are non-dominates
                        neighbors[ind].Add(offSpring[0]);
                        offSpring[0].Location = -1;
                        Ranking rank = new Ranking(neighbors[ind]);
                        for (int j = 0; j < rank.GetNumberOfSubfronts(); j++)
                        {
                            distance.CrowdingDistanceAssignment(rank.GetSubfront(j), this.Problem.NumberOfObjectives);
                        }
                        Solution worst = neighbors[ind].Worst(crowdingComparator);

                        if (worst.Location == -1)
                        {                        //The worst is the offspring
                            archive.Add(new Solution(offSpring[0]));
                        }
                        else
                        {
                            offSpring[0].Location = worst.Location;
                            currentPopulation.Replace(offSpring[0].Location, offSpring[0]);
                            archive.Add(new Solution(offSpring[0]));
                        }
                    }
                }

                //Store a portion of the archive into the population
                distance.CrowdingDistanceAssignment(archive, this.Problem.NumberOfObjectives);
                for (int j = 0; j < feedBack; j++)
                {
                    if (archive.Size() > j)
                    {
                        int r = JMetalRandom.Next(0, currentPopulation.Size() - 1);
                        if (r < currentPopulation.Size())
                        {
                            Solution individual = archive.Get(j);
                            individual.Location = r;
                            currentPopulation.Replace(r, new Solution(individual));
                        }
                    }
                }
            }
            Result = archive;
            return(archive);
        }
Example #22
0
        /// <summary>
        /// Perform the crossover operation
        /// </summary>
        /// <param name="probability">Crossover probability</param>
        /// <param name="parent1">The first parent</param>
        /// <param name="parent2">The second parent</param>
        /// <returns>Two offspring solutions</returns>
        private Solution[] DoCrossover(double probability, Solution parent1, Solution parent2)
        {
            Solution[] offspring = new Solution[2];

            offspring[0] = new Solution(parent1);
            offspring[1] = new Solution(parent2);

            if (parent1.Type.GetType() == typeof(PermutationSolutionType))
            {
                if (JMetalRandom.NextDouble() < probability)
                {
                    int   crosspoint1;
                    int   crosspoint2;
                    int   permutationLength;
                    int[] parent1Vector;
                    int[] parent2Vector;
                    int[] offspring1Vector;
                    int[] offspring2Vector;

                    permutationLength = ((Permutation)parent1.Variable[0]).Size;
                    parent1Vector     = ((Permutation)parent1.Variable[0]).Vector;
                    parent2Vector     = ((Permutation)parent2.Variable[0]).Vector;
                    offspring1Vector  = ((Permutation)offspring[0].Variable[0]).Vector;
                    offspring2Vector  = ((Permutation)offspring[1].Variable[0]).Vector;

                    // STEP 1: Get two cutting points
                    crosspoint1 = JMetalRandom.Next(0, permutationLength - 1);
                    crosspoint2 = JMetalRandom.Next(0, permutationLength - 1);

                    while (crosspoint2 == crosspoint1)
                    {
                        crosspoint2 = JMetalRandom.Next(0, permutationLength - 1);
                    }

                    if (crosspoint1 > crosspoint2)
                    {
                        int swap;
                        swap        = crosspoint1;
                        crosspoint1 = crosspoint2;
                        crosspoint2 = swap;
                    }

                    // STEP 2: Obtain the first child
                    int m = 0;
                    for (int j = 0; j < permutationLength; j++)
                    {
                        bool exist = false;
                        int  temp  = parent2Vector[j];
                        for (int k = crosspoint1; k <= crosspoint2; k++)
                        {
                            if (temp == offspring1Vector[k])
                            {
                                exist = true;
                                break;
                            }
                        }

                        if (!exist)
                        {
                            if (m == crosspoint1)
                            {
                                m = crosspoint2 + 1;
                            }
                            offspring1Vector[m++] = temp;
                        }
                    }

                    // STEP 3: Obtain the second child
                    m = 0;
                    for (int j = 0; j < permutationLength; j++)
                    {
                        bool exist = false;
                        int  temp  = parent1Vector[j];
                        for (int k = crosspoint1; k <= crosspoint2; k++)
                        {
                            if (temp == offspring2Vector[k])
                            {
                                exist = true;
                                break;
                            }
                        }
                        if (!exist)
                        {
                            if (m == crosspoint1)
                            {
                                m = crosspoint2 + 1;
                            }
                            offspring2Vector[m++] = temp;
                        }
                    }
                }
            }
            else
            {
                Logger.Log.Error("Exception in " + this.GetType().FullName + ".DoCrossover()");
                Console.WriteLine("Exception in " + this.GetType().FullName + ".DoCrossover()");
                throw new Exception("Exception in " + this.GetType().FullName + ".DoCrossover()");
            }

            return(offspring);
        }
Example #23
0
        public override SolutionSet Execute()
        {
            double contrDE       = 0;
            double contrSBX      = 0;
            double contrPol      = 0;
            double contrTotalDE  = 0;
            double contrTotalSBX = 0;
            double contrTotalPol = 0;

            double[] contrReal = new double[3];
            contrReal[0] = contrReal[1] = contrReal[2] = 0;

            IComparer <Solution> dominance          = new DominanceComparator();
            IComparer <Solution> crowdingComparator = new CrowdingComparator();
            Distance             distance           = new Distance();

            Operator selectionOperator;

            //Read parameter values
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "maxEvaluations", ref maxEvaluations);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "populationSize", ref populationSize);

            //Init the variables
            population  = new SolutionSet(populationSize);
            evaluations = 0;

            selectionOperator = Operators["selection"];

            Offspring[] getOffspring;
            int         N_O;     // number of offpring objects

            getOffspring = ((Offspring[])GetInputParameter("offspringsCreators"));
            N_O          = getOffspring.Length;

            contribution        = new double[N_O];
            contributionCounter = new int[N_O];

            contribution[0] = (double)(populationSize / (double)N_O) / (double)populationSize;
            for (int i = 1; i < N_O; i++)
            {
                contribution[i] = (double)(populationSize / (double)N_O) / (double)populationSize + (double)contribution[i - 1];
            }

            for (int i = 0; i < N_O; i++)
            {
                Console.WriteLine(getOffspring[i].Configuration());
                Console.WriteLine("Contribution: " + contribution[i]);
            }

            // Create the initial solutionSet
            Solution newSolution;

            for (int i = 0; i < populationSize; i++)
            {
                newSolution = new Solution(Problem);
                Problem.Evaluate(newSolution);
                Problem.EvaluateConstraints(newSolution);
                evaluations++;
                newSolution.Location = i;
                population.Add(newSolution);
            }

            while (evaluations < maxEvaluations)
            {
                // Create the offSpring solutionSet
                offspringPopulation = new SolutionSet(populationSize);
                Solution[] parents = new Solution[2];
                for (int i = 0; i < (populationSize / 1); i++)
                {
                    if (evaluations < maxEvaluations)
                    {
                        Solution individual = new Solution(population.Get(JMetalRandom.Next(0, populationSize - 1)));

                        int      selected  = 0;
                        bool     found     = false;
                        Solution offSpring = null;
                        double   rnd       = JMetalRandom.NextDouble();
                        for (selected = 0; selected < N_O; selected++)
                        {
                            if (!found && (rnd <= contribution[selected]))
                            {
                                if ("DE" == getOffspring[selected].Id)
                                {
                                    offSpring = getOffspring[selected].GetOffspring(population, i);
                                    contrDE++;
                                }
                                else if ("SBXCrossover" == getOffspring[selected].Id)
                                {
                                    offSpring = getOffspring[selected].GetOffspring(population);
                                    contrSBX++;
                                }
                                else if ("PolynomialMutation" == getOffspring[selected].Id)
                                {
                                    offSpring = ((PolynomialMutationOffspring)getOffspring[selected]).GetOffspring(individual);
                                    contrPol++;
                                }
                                else
                                {
                                    Logger.Log.Error("Error in NSGAIIAdaptive. Operator " + offSpring + " does not exist");
                                    Console.WriteLine("Error in NSGAIIAdaptive. Operator " + offSpring + " does not exist");
                                }

                                offSpring.Fitness = (int)selected;
                                found             = true;
                            }
                        }

                        Problem.Evaluate(offSpring);
                        offspringPopulation.Add(offSpring);
                        evaluations += 1;
                    }
                }

                // Create the solutionSet union of solutionSet and offSpring
                union = ((SolutionSet)population).Union(offspringPopulation);

                // Ranking the union
                Ranking ranking = new Ranking(union);

                int         remain = populationSize;
                int         index  = 0;
                SolutionSet front  = null;
                population.Clear();

                // Obtain the next front
                front = ranking.GetSubfront(index);

                while ((remain > 0) && (remain >= front.Size()))
                {
                    //Assign crowding distance to individuals
                    distance.CrowdingDistanceAssignment(front, Problem.NumberOfObjectives);
                    //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
                    distance.CrowdingDistanceAssignment(front, Problem.NumberOfObjectives);
                    front.Sort(new CrowdingComparator());
                    for (int k = 0; k < remain; k++)
                    {
                        population.Add(front.Get(k));
                    }

                    remain = 0;
                }

                // CONTRIBUTION CALCULATING PHASE
                // First: reset contribution counter
                for (int i = 0; i < N_O; i++)
                {
                    contributionCounter[i] = 0;
                }

                // Second: determine the contribution of each operator
                for (int i = 0; i < population.Size(); i++)
                {
                    if ((int)population.Get(i).Fitness != -1)
                    {
                        contributionCounter[(int)population.Get(i).Fitness] += 1;
                    }
                    population.Get(i).Fitness = -1;
                }

                contrTotalDE  += contributionCounter[0];
                contrTotalSBX += contributionCounter[1];
                contrTotalPol += contributionCounter[2];

                int minimumContribution      = 2;
                int totalContributionCounter = 0;

                for (int i = 0; i < N_O; i++)
                {
                    if (contributionCounter[i] < minimumContribution)
                    {
                        contributionCounter[i] = minimumContribution;
                    }
                    totalContributionCounter += contributionCounter[i];
                }

                if (totalContributionCounter == 0)
                {
                    for (int i = 0; i < N_O; i++)
                    {
                        contributionCounter[i] = 10;
                    }
                }

                // Third: calculating contribution
                contribution[0] = contributionCounter[0] * 1.0
                                  / (double)totalContributionCounter;
                for (int i = 1; i < N_O; i++)
                {
                    contribution[i] = contribution[i - 1] + 1.0 * contributionCounter[i] / (double)totalContributionCounter;
                }
            }

            // Return the first non-dominated front
            Ranking rank = new Ranking(population);

            Result = rank.GetSubfront(0);
            return(Result);
        }
Example #24
0
        public Solution[] DoCrossover(double probability, Solution parent1, Solution parent2)
        {
            Solution[] offspring = new Solution[2];

            offspring[0] = new Solution(parent1);
            offspring[1] = new Solution(parent2);

            int permutationLength = ((Permutation)parent1.Variable[0]).Size;

            int[] parent1Vector    = ((Permutation)parent1.Variable[0]).Vector;
            int[] parent2Vector    = ((Permutation)parent2.Variable[0]).Vector;
            int[] offspring1Vector = ((Permutation)offspring[0].Variable[0]).Vector;
            int[] offspring2Vector = ((Permutation)offspring[1].Variable[0]).Vector;

            if (JMetalRandom.NextDouble() < probability)
            {
                int cuttingPoint1;
                int cuttingPoint2;

                // STEP 1: Get two cutting points
                cuttingPoint1 = JMetalRandom.Next(0, permutationLength - 1);
                cuttingPoint2 = JMetalRandom.Next(0, permutationLength - 1);

                while (cuttingPoint1 == cuttingPoint2)
                {
                    cuttingPoint2 = JMetalRandom.Next(0, permutationLength - 1);
                }

                if (cuttingPoint1 > cuttingPoint2)
                {
                    int swap;
                    swap          = cuttingPoint1;
                    cuttingPoint1 = cuttingPoint2;
                    cuttingPoint2 = swap;
                }

                // STEP 2: Get the subchains to interchange
                int[] replacement1 = new int[permutationLength];
                int[] replacement2 = new int[permutationLength];
                for (int i = 0; i < permutationLength; i++)
                {
                    replacement1[i] = replacement2[i] = -1;
                }

                // STEP 3: Interchange

                for (int i = cuttingPoint1; i <= cuttingPoint2; i++)
                {
                    offspring1Vector[i] = parent2Vector[i];
                    offspring2Vector[i] = parent1Vector[i];

                    replacement1[parent2Vector[i]] = parent1Vector[i];
                    replacement2[parent1Vector[i]] = parent2Vector[i];
                }

                // STEP 4: Repair offsprings

                for (int i = 0; i < permutationLength; i++)
                {
                    if ((i >= cuttingPoint1) && (i <= cuttingPoint2))
                    {
                        continue;
                    }

                    int n1 = parent1Vector[i];
                    int m1 = replacement1[n1];

                    int n2 = parent2Vector[i];
                    int m2 = replacement2[n2];

                    while (m1 != -1)
                    {
                        n1 = m1;
                        m1 = replacement1[m1];
                    }
                    while (m2 != -1)
                    {
                        n2 = m2;
                        m2 = replacement2[m2];
                    }

                    offspring1Vector[i] = n1;
                    offspring2Vector[i] = n2;
                }
            }

            return(offspring);
        }