Ejemplo n.º 1
0
        /// <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 override SolutionSet Execute()
        {
            // !!!! NEEDED PARAMETES !!! start
            //J* Parameters
            int populationSize = -1; // J* store population size
            int maxEvaluations = -1; // J* store number of max Evaluations
            int evaluations;         // J* number of current evaluations

            // J* Objects needed to illustrate the use of quality indicators inside the algorithms
            QualityIndicator indicators = null; // QualityIndicator object
            int requiredEvaluations;            // Use in the example of use of the
            // indicators object (see below)

            // J* populations needed to implement NSGA-II
            SolutionSet population;          //J* Current population
            SolutionSet offspringPopulation; //J* offspring population
            SolutionSet union;               //J* population resultant from current and offpring population

            //J* Genetic Operators
            Operator mutationOperator;
            Operator crossoverOperator;
            Operator selectionOperator;

            //J* Used to evaluate crowding distance
            Distance distance = new Distance();

            //J* !!!! NEEDED PARAMETES !!! end

            //J* !!! INITIALIZING PARAMETERS - start !!!

            //Read the parameters
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "maxEvaluations", ref maxEvaluations);  //J* required
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "populationSize", ref populationSize);  //J* required
            JMetalCSharp.Utils.Utils.GetIndicatorsFromParameters(this.InputParameters, "indicators", ref indicators);       //J* optional

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

            requiredEvaluations = 0;

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

            //J* !!! INITIALIZING PARAMETERS - end !!!


            //J* !!! Creating first population !!!

            JMetalRandom.SetRandom(comp.MyRand);
            comp.LogAddMessage("Random seed = " + comp.Seed);

            // Create the initial solutionSet
            Solution newSolution;

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

            // Generations
            while (evaluations < maxEvaluations)
            {
                // Create the offSpring solutionSet
                offspringPopulation = new SolutionSet(populationSize);
                Solution[] parents = new Solution[2];
                for (int i = 0; i < (populationSize / 2); i++)
                {
                    if (evaluations < maxEvaluations)
                    {
                        //obtain parents
                        parents[0] = (Solution)selectionOperator.Execute(population);
                        parents[1] = (Solution)selectionOperator.Execute(population);
                        Solution[] offSpring = (Solution[])crossoverOperator.Execute(parents);
                        mutationOperator.Execute(offSpring[0]);
                        mutationOperator.Execute(offSpring[1]);
                        Problem.Evaluate(offSpring[0]);
                        Problem.EvaluateConstraints(offSpring[0]);
                        Problem.Evaluate(offSpring[1]);
                        Problem.EvaluateConstraints(offSpring[1]);
                        offspringPopulation.Add(offSpring[0]);
                        offspringPopulation.Add(offSpring[1]);
                        evaluations += 2;
                    }
                }

                // 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;
                }

                // This piece of code shows how to use the indicator object into the code
                // of NSGA-II. In particular, it finds the number of evaluations required
                // by the algorithm to obtain a Pareto front with a hypervolume higher
                // than the hypervolume of the true Pareto front.
                if ((indicators != null) && (requiredEvaluations == 0))
                {
                    double HV = indicators.GetHypervolume(population);
                    if (HV >= (0.98 * indicators.TrueParetoFrontHypervolume))
                    {
                        requiredEvaluations = evaluations;
                    }
                }
            }



            // Return as output parameter the required evaluations
            SetOutputParameter("evaluations", requiredEvaluations);

            comp.LogAddMessage("Evaluations = " + evaluations);
            // Return the first non-dominated front
            Ranking rank = new Ranking(population);

            Result = rank.GetSubfront(0);

            return(Result);
        }
Ejemplo n.º 2
0
        /// <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 override SolutionSet Execute()
        {
            int populationSize = -1;
            int maxEvaluations = -1;
            int evaluations;

            QualityIndicator.QualityIndicator indicators = null; // QualityIndicator object
            int requiredEvaluations;                             // Use in the example of use of the
            // indicators object (see below)

            SolutionSet population;
            SolutionSet offspringPopulation;
            SolutionSet union;

            Operator mutationOperator;
            Operator crossoverOperator;
            Operator selectionOperator;

            Distance distance = new Distance();

            //Read the parameters
            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);

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

            requiredEvaluations = 0;

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

            Random random = new Random(2);

            JMetalRandom.SetRandom(random);

            // Create the initial solutionSet
            Solution newSolution;

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

            // Generations
            while (evaluations < maxEvaluations)
            {
                // Create the offSpring solutionSet
                offspringPopulation = new SolutionSet(populationSize);
                Solution[] parents = new Solution[2];
                for (int i = 0; i < (populationSize / 2); i++)
                {
                    if (evaluations < maxEvaluations)
                    {
                        //obtain parents
                        parents[0] = (Solution)selectionOperator.Execute(population);
                        parents[1] = (Solution)selectionOperator.Execute(population);
                        Solution[] offSpring = (Solution[])crossoverOperator.Execute(parents);
                        mutationOperator.Execute(offSpring[0]);
                        mutationOperator.Execute(offSpring[1]);
                        Problem.Evaluate(offSpring[0]);
                        Problem.EvaluateConstraints(offSpring[0]);
                        Problem.Evaluate(offSpring[1]);
                        Problem.EvaluateConstraints(offSpring[1]);
                        offspringPopulation.Add(offSpring[0]);
                        offspringPopulation.Add(offSpring[1]);
                        evaluations += 2;
                    }
                }

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


                var list   = union.SolutionsList;
                var unique = list.Distinct(new ComparerP()).ToList();

                union = new SolutionSet(unique.Count);
                union.SolutionsList.AddRange(unique);

                //ConfigurationSolutionType.AllSolutions = new object ();

                // 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;
                }

                // This piece of code shows how to use the indicator object into the code
                // of NSGA-II. In particular, it finds the number of evaluations required
                // by the algorithm to obtain a Pareto front with a hypervolume higher
                // than the hypervolume of the true Pareto front.
                if ((indicators != null) && (requiredEvaluations == 0))
                {
                    double HV = indicators.GetHypervolume(population);
                    if (HV >= (0.98 * indicators.TrueParetoFrontHypervolume))
                    {
                        requiredEvaluations = evaluations;
                    }
                }
            }

            // Return as output parameter the required evaluations
            SetOutputParameter("evaluations", requiredEvaluations);


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

            Result = rank.GetSubfront(0);

            return(population);
        }
Ejemplo n.º 3
0
        /// <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 override SolutionSet Execute()
        {
            int populationSize   = -1;
            int maxEvaluations   = -1;
            int iterationsNumber = -1;
            int evaluations;
            int iteration;

            QualityIndicator.QualityIndicator indicators = null; // QualityIndicator object
            int requiredEvaluations;                             // Use in the example of use of the
            // indicators object (see below)

            SolutionSet population;
            SolutionSet offspringPopulation;
            SolutionSet union;

            Operator mutationOperator;
            Operator crossoverOperator;
            Operator selectionOperator;

            Distance distance = new Distance();

            //Read the parameters
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "maxEvaluations", ref maxEvaluations);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "populationSize", ref populationSize);
            JMetalCSharp.Utils.Utils.GetIntValueFromParameter(this.InputParameters, "iterationsNumber", ref iterationsNumber);
            JMetalCSharp.Utils.Utils.GetIndicatorsFromParameters(this.InputParameters, "indicators", ref indicators);

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

            requiredEvaluations = 0;

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

            Random random = new Random();

            JMetalRandom.SetRandom(random);

            // Create the initial solutionSet
            Solution newSolution;

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

            /*
             * string dir = "Result/MOEAD_ACOR/ZDT4_Real/Record/NSGAII_SBX_nr16";
             * if (Directory.Exists(dir))
             * {
             *  Console.WriteLine("The directory {0} already exists.", dir);
             * }
             * else
             * {
             *  Directory.CreateDirectory(dir);
             *  Console.WriteLine("The directory {0} was created.", dir);
             * }*/

            // Generations
            while (iteration < iterationsNumber)
            {
                // Create the offSpring solutionSet
                offspringPopulation = new SolutionSet(populationSize);
                Solution[] parents = new Solution[2];
                for (int i = 0; i < (populationSize / 2); i++)
                {
                    if (iteration < iterationsNumber)
                    {
                        //obtain parents
                        parents[0] = (Solution)selectionOperator.Execute(population);
                        parents[1] = (Solution)selectionOperator.Execute(population);
                        Solution[] offSpring = (Solution[])crossoverOperator.Execute(parents);
                        mutationOperator.Execute(offSpring[0]);
                        mutationOperator.Execute(offSpring[1]);
                        Problem.Evaluate(offSpring[0]);
                        Problem.EvaluateConstraints(offSpring[0]);
                        Problem.Evaluate(offSpring[1]);
                        Problem.EvaluateConstraints(offSpring[1]);
                        offspringPopulation.Add(offSpring[0]);
                        offspringPopulation.Add(offSpring[1]);
                        evaluations += 2;
                    }
                }

                // 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;
                }

                /*
                 * string filevar = dir + "/VAR" + iteration;
                 * string filefun = dir + "/FUN" + iteration;
                 * population.PrintVariablesToFile(filevar);
                 * population.PrintObjectivesToFile(filefun);*/

                iteration++;

                // This piece of code shows how to use the indicator object into the code
                // of NSGA-II. In particular, it finds the number of evaluations required
                // by the algorithm to obtain a Pareto front with a hypervolume higher
                // than the hypervolume of the true Pareto front.
                if ((indicators != null) && (requiredEvaluations == 0))
                {
                    double HV = indicators.GetHypervolume(population);
                    if (HV >= (0.98 * indicators.TrueParetoFrontHypervolume))
                    {
                        requiredEvaluations = evaluations;
                    }
                }
            }

            Logger.Log.Info("ITERATION: " + iteration);
            Console.WriteLine("ITERATION: " + iteration);

            // Return as output parameter the required evaluations
            SetOutputParameter("evaluations", requiredEvaluations);

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

            Result = rank.GetSubfront(0);

            return(Result);
        }