FunctionMax

The problem is to maximize the following function of variables x and y:


    f = (x^2 + y^2)^(1/2)

In addition, x and y must be between -100 and 100.

Real solution: 141.42136 with x=-100 and y=-100 or x=-100 and y=100 or x=100 and y=100 or x=100 and y=-100

Code:


    var cor = new Cormorant();

    // Create genes
    var genX = new Gene("x", -100d, 100d);
    var genY = new Gene("y", -100d, 100d);

    // Create the genome and set the genes and the genome
    var genome = new Genome();
    genome.SetGene(genX);
    genome.SetGene(genY);
    cor.SetGenome(genome);

    // Set some properties
    cor.SetNumberGenerations(50);
    cor.SetPopulationSize(50);
    cor.SetFitnessFunction(FitnessFunction);
    cor.SetMaintain(5);
    cor.SetMutation(15);

    // Optional and just for test purpose: set the solution if it is known to get the absolute and relative error
    cor.SetSolution(141.42136);

    // Compute the algorithm
    cor.Compute();

    // Show the report
    Console.WriteLine(cor.GetReport());

    private static double FitnessFunction(Individual individual)
    {
        var genX = individual.Genotype.GetGeneByName("x").Value;
        var genY = individual.Genotype.GetGeneByName("y").Value;

        // Function: f = (x^2 + x^2)^(1/2)
        var result = Math.Sqrt(Math.Pow(genX, 2) + Math.Pow(genY, 2));

        return result;
    }

Output:


    ==================================================
    Parameters
    ==================================================
    Population size: 50
    Generations: 50
    Maintain: 5%
    Mutation: 15%
    Fitness type: Maximize
    Crossover type: OnePoint

    ==================================================
    Best individual by generation
    ==================================================
    Generation 0:   * 136,62290930443666
    Generation 1:   * 136,62290930443666
    Generation 2:   * 136,62290930443666
    Generation 3:   * 136,62290930443666
    Generation 4:   ********************* 140,29694450867675
    Generation 5:   ********************* 140,29694450867675
    Generation 6:   ********************* 140,29694450867675
    Generation 7:   ********************* 140,29694450867675
    Generation 8:   ********************* 140,29694450867675
    Generation 9:   ********************* 140,29694450867675
    Generation 10:  ********************* 140,29694450867675
    Generation 11:  ********************* 140,29694450867675
    Generation 12:  ********************* 140,29694450867675
    Generation 13:  ********************* 140,29694450867675
    Generation 14:  ********************* 140,29694450867675
    Generation 15:  ********************* 140,29694450867675
    Generation 16:  ********************* 140,29694450867675
    Generation 17:  ********************* 140,29694450867675
    Generation 18:  ********************* 140,29694450867675
    Generation 19:  ********************* 140,29694450867675
    Generation 20:  ********************* 140,29694450867675
    Generation 21:  ********************* 140,29694450867675
    Generation 22:  ********************* 140,29694450867675
    Generation 23:  ************************** 141,20236485076495
    Generation 24:  ************************** 141,20236485076495
    Generation 25:  ************************** 141,20236485076495
    Generation 26:  ************************** 141,20236485076495
    Generation 27:  ************************** 141,20236485076495
    Generation 28:  ************************** 141,20236485076495
    Generation 29:  ************************** 141,20236485076495
    Generation 30:  ************************** 141,20236485076495
    Generation 31:  ************************** 141,20236485076495
    Generation 32:  ************************** 141,20236485076495
    Generation 33:  ************************** 141,20236485076495
    Generation 34:  ************************** 141,20236485076495
    Generation 35:  ************************** 141,20236485076495
    Generation 36:  ************************** 141,20236485076495
    Generation 37:  ************************** 141,20236485076495
    Generation 38:  ************************** 141,20236485076495
    Generation 39:  ************************** 141,20236485076495
    Generation 40:  ************************** 141,20236485076495
    Generation 41:  ************************** 141,20236485076495
    Generation 42:  ************************** 141,20236485076495
    Generation 43:  ************************** 141,20236485076495
    Generation 44:  ************************** 141,20236485076495
    Generation 45:  ************************** 141,22465435877032
    Generation 46:  *************************** 141,25388443440247
    Generation 47:  *************************** 141,25388443440247
    Generation 48:  *************************** 141,25388443440247
    Generation 49:  *************************** 141,25388443440247
    Generation 50:  *************************** 141,25388443440247

    ==================================================
    Best individual
    ==================================================
    Fitness: 141,25388443440247
    Genotype:
    - Gene x, Value: -99,85396962347866
    - Gene y, Value: -99,90918185152418

    ==================================================
    Errors
    ==================================================
    Absolute error: 0,16747556559752752
    Relative error: 0,11842310496627066 %