遗传算法解释及代码一看就懂

GAGeneticAlgorithm一.个体基因Gene：染色体Chromosome)生存竞争，适者生存B的个体参加繁殖的机会比简朴说来就是：繁殖过程，会发生基因交叉Crossover)(Mutation)，适应度(Fitness)低的个体会被逐步裁减，而适应度高的个体N代的自然选择后，保存下来的个体都是适应度很高的，二.N代后就很有可能会进化出适应度函数值举个例子，使用遗传算法解决“0-1背包问题”的思路：0-1背包的解能够编0-1字符串（0：不取，1：取）M0-1字符串，0-10-1背包问题的解的优劣；然后，随机选择某些M个字符串，并且较优的解被选中G代的进化后就可能会产生出0-1“近0-1字符串作为0-1背包问题的解就属于二进制编码。3选择“比例选择”，也就是个体被选中的概率与其适应度函数值成正比。假设群体的个体总数是M，Xif(Xi)/(f(X1)+f(X2)+……..+f(Xn))。比例选择实现算法就是所谓的“轮盘赌算法RouletteWheelSelection，P[i]iint{mr=Random(0,1//r01for(i=1;i<=N;i++){/*m~m+P[i]im=m+P[i];if(r<=m)returni;}}PcPm。例如：(FitnessFunction)f(x)三.Pc：Pm：{初始化空种群newPop{if(random(0,1)<Pc){}if(random(0,1)<Pm{}untilM}untilTf，G四.五.AForge.GeneticTSP构。AForge.NET中包含有一种遗传算法的类库。AForge.NET主页：介绍一下AForgeAForge.Genetic1.AForge.Genetic31个省会都市的坐标:过“AddReference...”DLL添加到工程。31bin/Debug/Data.txtusingusingusingnamespace{///FitnessfunctionforTSPtask(TravalingSalasmanpublicclassTSPFitnessFunction:{//privateint[,]map//publicTSPFitnessFunction(int[,]{this.map=}///Evaluatechromosome-calculatesitsfitnesspublicdoubleEvaluate(IChromosome{return1/(PathLength(chromosome)}///TranslategenotypetopublicobjectTranslate(IChromosome{returnTSPFitnessFunction}///CalculatepathlengthrepresentedbythespecifiedpublicdoublePathLength(IChromosome{//salesmanushort[]path=//checkpathif(path.Length!={thrownewArgumentException("Invalidpathspecified-notallcitiesare}//pathintprev=intcurr=path[path.Length-//calculatedistancebetweenthelastandthefirstcitydoubledx=map[curr,0]-map[prev,0];doubledy=map[curr,1]-map[prev,doublepathLength=Math.Sqrt(dx*dx+dy*//calculatethepathlengthfromthefirstcitytothelastfor(inti=1,n=path.Length;i<n;i++){//getcurrentcitycurr=path[i];//calculatedx=map[curr,0]-map[prev,0];dy=map[curr,1]-map[prev,pathLength+=Math.Sqrt(dx*dx+dy*//putcurrentcityaspreviousprev=curr;}return}}}}GenticTSPGenticTSPusingusingSystem.Collections.Generic;usingSystem.Linq;usingSystem.Text;usingSystem.IO;usingusingnamespace{class{staticvoid{StreamReaderreadernewStreamReader("Data.txt");intcitiesCount=31;//都市数int[,]map=newint[citiesCount,for(inti=0;i<citiesCount;{stringvalue=reader.ReadLine();string[]temp=value.Split('');map[i,0int.Parse(temp[0//读取都市坐标map[i,1]=int.Parse(temp[1]);}//createfitnessTSPFitnessFunctionfitnessFunctionnewTSPFitnessFunction(map);intpopulationSize=1000;//种群最大规模0：EliteSelection1：RankSelection其它：RouletteWheelSelectionintselectionMethod//createPopulationpopulation=newPopulation(populationSize,newPermutationChromosome(citiesCount),(selectionMethod==0)?(ISelectionMethod)newEliteSelection():(selectionMethod==1)?(ISelectionMethod)newRankSelection():(ISelectionMethod)newRouletteWheelSelection()//iterationsint