Question

所以基本上我正在创建一个遗传算法但是在实现交叉代码时我很困难。任何人都可以伸出援助之手让我知道，如果我的代码在实施第一阶段交叉时朝着正确的方向迈出了一步。或者任何人都可以给我订购一个交叉的伪代码吗？

package geneticalgorithm;

import java.util.Random;

public class GeneticAlgorithm {

final static int P = 20;
final static int N = 10;
static int popFitness = 0;  
int offspringFitness = 0;
static Random rand = new Random();
static int count = 0;

   static Individual[]  population = new Individual[P];
   static Individual[] offspring = new Individual[P];


public static void main(String[] args) {



    for (int i = 0; i < P; i++){


        population[i] = new Individual(); //Generates a population of P individuals and gives each one unique genes
        population[i].generateGenes();
        population[i].fitness = 0;
    }

    for (int i = 0; i < P; i++){
        for (int j = 0; j < N; j++){                //    Loops through each individual in the population and assesses their
            if (population[i].genes[j] == 1 ){       //fitness based on how many 1's are in its genes
                population[i].fitness++;

            }
        }    
    }  

    for (int i = 0; i < P ; i++){
     for (int j = 0; j < N; j++){
         count++;

        System.out.print(population[i].genes[j]  ); // Loops through population and each gene and outputs each individuals genes to the screen aswell as there fitness
     if ((count % N) == 0){
         System.out.print( "    " + population[i].fitness);
         System.out.println("");
     }
    }
    }




    for (int i = 0; i < P; i++){

        popFitness += population[i].fitness; // calculates the overall fitness of the population
    }

    System.out.println(popFitness);


   offspring[1] = population[rouletteSelection()];
    System.out.println(offspring[1]);

    for (int i = 0; i < P; i++){

        int p1 = rand.nextInt(P);
        int p2 = rand.nextInt(P);

        if (population[p1].fitness >= population[p2].fitness){
                offspring[i] = population[p1];
        }
            else {                                       //Randomly creates a new population called offspring by comparing two random parents 
                offspring[i] = population[p2];          //and picking the one with the largest fitness value
                        }

        }


} 




 public static Individual crossover1(Individual parent1, Individual parent2){
    Individual newSol = new Individual();
    parent1 = population[rouletteSelection()];
    parent2 = population[rouletteSelection()];
    int crossoverPoint = rand.nextInt(N);
    for (int j = 0; j < N; j++){
        Individual newSolution = new Individual();

    for (int i = 0; i == crossoverPoint; i++){

        newSolution.setGenes(i, parent1.getGenes(i));
        }
    for (int i = crossoverPoint; i < N; i++){
        newSolution.setGenes(i, parent2.getGenes(i));
    }
    }
return null;} 



public static int rouletteSelection(){
int parent = 0;
int randNum = rand.nextInt(popFitness);
int rollingSum = 0;
for (int i = 0; i < P; i++){
    rollingSum += population[i].fitness;  //Algorithm to select a         parent based on probability and a hint of randomness
    if (rollingSum >= randNum){
         parent = i;
        break;
    }
 } System.out.println(parent);
 return parent;

}



}

Answer 1

您的交叉功能对我来说看起来不错，但是您似乎再也不会返回新的个人了：

public static Individual crossover1(Individual parent1, Individual parent2){
     Individual newSol = new Individual();
     parent1 = population[rouletteSelection()];
     parent2 = population[rouletteSelection()];
     int crossoverPoint = rand.nextInt(N);
     for (int j = 0; j < N; j++){

     for (int i = 0; i == crossoverPoint; i++){

         newSol.setGenes(i, parent1.getGenes(i));
      }
    for (int i = crossoverPoint; i < N; i++){
       newSol.setGenes(i, parent2.getGenes(i));
     }
    }
    return newSol;
}

Java遗传算法中的一阶交叉

1 个答案: