遺傳算法C語言代碼

//GA.cpp:Definestheentrypointfortheconsoleapplication.///*這是一個非常簡單的遺傳算法源代碼，是由DenisCormier(NorthCarolinaStateUniversity)開發(fā)的，SitaS.Raghavan(UniversityofNorthCarolinaatCharlotte修正。代碼保證盡可能少，實際上也不必查錯。對一特定的應用修正此代碼，用戶只需改變常數(shù)的定義并且定義“評價函數(shù)”即可。注意代碼的設計是求最大值，其中的目標函數(shù)只能取正值；且函數(shù)值和個體的適應值之間沒有區(qū)別。該系統(tǒng)使用比率選擇、精華模型、單點雜交和均勻變異。如果用Gaussian變異替換均勻變異，可能得到更好的效果。代碼沒有任何圖形，甚至也沒有屏幕輸出，主要是保證在平臺之間的高可移植性。讀者可以從,目錄coe/evol中的文件prog.c中獲得。要求輸入的文件應該命名為‘gadata.txt’；系統(tǒng)產(chǎn)生的輸出文件為‘galog.txt’。輸入的文件由幾行組成：數(shù)目對應于變量數(shù)。且每一行提供次序一一對應于變量的上下界。如第一行為第一個變量提供上下界，第二行為第二個變量提供上下界，等等。*/#include<stdio.h>#include<stdlib.h>#include<math.h>/*Changeanyoftheseparameterstomatchyourneeds*/〃請根據(jù)你的需要來修改以下參數(shù)#definePOPSIZE50/*populationsize種群大小*/#defineMAXGENS1000/*max.numberofgenerations最大基因個數(shù)*/constintNVARS=3;/*no.ofproblemvariables問題變量的個數(shù)*/#definePXOVER0.8/*probabilityofcrossover雜交概率*/#definePMUTATION0.15/*probabilityofmutation變異概率*/#defineTRUE1#defineFALSE0intgeneration;/*currentgenerationno.當前基因個數(shù)*/intcur_best;/*bestindividual最優(yōu)個體*/FILE*galog;/*anoutputfile輸出文件指針*/structgenotype/*genotype(GT),amemberofthepopulation種群的一個基因的結構體類型*/{doublegene[NVARS];/*astringofvariables變量*/doublefitness;/*GT'sfitness基因的適應度*/doubleupper[NVARS];/*GT'svariablesupperbound基因變量的上界*/doublelower[NVARS];/*GT'svariableslowerbound基因變量的下界*/doublerfitness;/*relativefitness比較適應度*/doublecfitness;/*cumulativefitness積累適應度*/};structgenotypepopulation[POPSIZE+1];/*population種群*/structgenotypenewpopulation[POPSIZE+1];/*newpopulation;新種群*//*replacestheoldgeneration*///取代舊的基因/*Declarationofproceduresusedbythisgeneticalgorithm*///以下是一些函數(shù)聲明voidinitialize(void);doublerandval(double,double);voidevaluate(void);voidkeep_the_best(void);voidelitist(void);voidselect(void);voidcrossover(void);voidXover(int,int);voidswap(double*,double*);voidmutate(void);voidreport(void);/*Initializationfunction:Initializesthevaluesofgenes*//*withinthevariablesbounds.Italsoinitializes(tozero)*//*allfitnessvaluesforeachmemberofthepopulation.It*//*readsupperandlowerboundsofeachvariablefromthe*//*inputfile'gadata.txt'.Itrandomlygeneratesvalues*//*betweentheseboundsforeachgeneofeachgenotypeinthe*//*population.Theformatoftheinputfile'gadata.txt'is*//*var1_lower_boundvar1_upperbound*//*var2_lower_boundvar2_upperbound...*/voidinitialize(void){FILE*infile;inti,j;doublelbound,ubound;if((infile=fopen("gadata.txt","r"))==NULL){fprintf(galog,"\nCannotopeninputfile!\n");exit(1);}/*initializevariableswithinthebounds*///把輸入文件的變量界限輸入到基因結構體中for(i=0;i<NVARS;i++){fscanf(infile,"%lf",&lbound);fscanf(infile,"%lf",&ubound);for(j=0;j<POPSIZE;j++){population[j].fitness=0;population[j].rfitness=0;population[j].cfitness=0;population[j].lower[i]=lbound;population[j].upper[i]=ubound;population[j].gene[i]=randval(population[j].lower[i],population[j].upper[i]);}}fclose(infile);}/*Randomvaluegenerator:Generatesavaluewithinbounds*///隨機數(shù)產(chǎn)生函數(shù)doublerandval(doublelow,doublehigh){doubleval;val=((double)(rand()%1000)/1000.0)*(high-low)+low;return(val);/*Evaluationfunction:Thistakesauserdefinedfunction.*//*Eachtimethisischanged,thecodehastoberecompiled.*//*Thecurrentfunctionis:x[1]A2-x[1]*x[2]+x[3]*///評價函數(shù)，可以由用戶自定義，該函數(shù)取得每個基因的適應度voidevaluate(void){intmem;inti;doublex[NVARS+1];for(mem=0;mem<POPSIZE;mem++){for(i=0;i<NVARS;i++)x[i+1]=population[mem].gene[i];population[mem].fitness=(x[1]*x[1])-(x[1]*x[2])+x[3];}}/"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""/***************************************************************/*Keep_the_bestfunction:Thisfunctionkeepstrackofthe*//*bestmemberofthepopulation.Notethatthelastentryin*//*thearrayPopulationholdsacopyofthebestindividual*//"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""/***************************************************************//保存每次遺傳后的最佳基因voidkeep_the_best(){intmem;inti;cur_best=0;/*storestheindexofthebestindividual*///保存最佳個體的索引for(mem=0;mem<POPSIZE;mem++){if(population[mem].fitness>population[POPSIZE].fitness){cur_best=mem;population[POPSIZE].fitness=population[mem].fitness;}}/*oncethebestmemberinthepopulationisfound,copythegenes*///一旦找到種群的最佳個體，就拷貝他的基因for(i=0;i<NVARS;i++)population[POPSIZE].gene[i]=population[cur_best].gene[i];}/""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""/****************************************************************/*Elitistfunction:Thebestmemberofthepreviousgeneration*//*isstoredasthelastinthearray.Ifthebestmemberof*//*thecurrentgenerationisworsethenthebestmemberofthe*//*previousgeneration,thelatteronewouldreplacetheworst*//*memberofthecurrentpopulation*///搜尋杰出個體函數(shù)：找出最好和最壞的個體。//如果某代的最好個體比前一代的最好個體要壞，那么后者將會取代當前種群的最壞個體voidelitist(){inti;doublebest,worst;/*bestandworstfitnessvalues最好和最壞個體的適應度值*/intbest_mem,worst_mem;/*indexesofthebestandworstmember最好和最壞個體的索引*/best=population[0].fitness;worst=population[0].fitness;for(i=0;i<POPSIZE-1;++i){if(population[i].fitness>population[i+1].fitness){if(population[i].fitness>=best){best=population[i].fitness;best_mem=i;}if(population[i+1].fitness<=worst){worst=population[i+1].fitness;worst_mem=i+1;}}else{if(population[i].fitness<=worst){worst=population[i].fitness;worst_mem=i;}if(population[i+1].fitness>=best){best=population[i+1].fitness;best_mem=i+1;}/*ifbestindividualfromthenewpopulationisbetterthan*//*thebestindividualfromthepreviouspopulation,then*//*copythebestfromthenewpopulation;elsereplacethe*//*worstindividualfromthecurrentpopulationwiththe*//*bestonefromthepreviousgeneration*/〃如果新種群中的最好個體比前一代的最好個體要強的話，那么就把新種群的最好個體拷貝出來?！ǚ駝t就用前一代的最好個體取代這次的最壞個體if(best>=population[POPSIZE].fitness){for(i=0;i<NVARS;i++)population[POPSIZE].gene[i]=population[best_mem].gene[i];population[POPSIZE].fitness=population[best_mem].fitness;}else{for(i=0;i<NVARS;i++)population[worst_mem].gene[i]=population[POPSIZE].gene[i];population[worst_mem].fitness=population[POPSIZE].fitness;}}/*Selectionfunction:Standardproportionalselectionfor*//*maximizationproblemsincorporatingelitistmodel-makes*//*surethatthebestmembersurvives*///選擇函數(shù)：用于最大化合并杰出模型的標準比例選擇，保證最優(yōu)秀的個體得以生存voidselect(void){intmem,j,i;doublesum=0;doublep;/*findtotalfitnessofthepopulation*/〃找出種群的適應度之和for(mem=0;mem<POPSIZE;mem++){sum+=population[mem].fitness;}/*calculaterelativefitness*///計算相對適應度for(mem=0;mem<POPSIZE;mem++){population[mem].rfitness=population[mem].fitness/sum;}population[0].cfitness=population[0].rfitness;/*calculatecumulativefitness*///計算累加適應度for(mem=1;mem<POPSIZE;mem++){population[mem].cfitness=population[mem-1].cfitness+population[mem].rfitness;}/*finallyselectsurvivorsusingcumulativefitness.*/〃用累加適應度作出選擇for(i=0;i<POPSIZE;i++){p=rand()%1000/1000.0;if(p<population[0].cfitness)newpopulation[i]=population[0];else{for(j=0;j<POPSIZE;j++)if(p>=population[j].cfitness&&p<population[j+1].cfitness)newpopulation[i]=population[j+1];}}/*onceanewpopulationiscreated,copyitback*/〃當一個新種群建立的時候，將其拷貝回去for(i=0;i<POPSIZE;i++)population[i]=newpopulation[i];}/*Crossoverselection:selectstwoparentsthattakepartin*//*thecrossover.Implementsasinglepointcrossover*///雜交函數(shù)：選擇兩個個體來雜交，這里用單點雜交voidcrossover(void){intmem,one;intfirst=0;/*countofthenumberofmemberschosen*/doublex;for(mem=0;mem<POPSIZE;++mem){x=rand()%1000/1000.0;if(x<PXOVER){++first;if(first%2==0)Xover(one,mem);elseone=mem;}}}/*Crossover:performscrossoverofthetwoselectedparents.*/voidXover(intone,inttwo){inti;intpoint;/*crossoverpoint*//*selectcrossoverpoint*/if(NVARS>1){if(NVARS==2)point=1;elsepoint=(rand()%(NVARS-1))+1;for(i=0;i<point;i++)swap(&population[one].gene[i],&population[two].gene[i]);}}/*Swap:Aswapprocedurethathelpsinswapping2variables*/voidswap(double*x,double*y){doubletemp;temp=*x;*x=*y;*y=temp;/*Mutation:Randomuniformmutation.Avariableselectedfor*//*mutationisreplacedbyarandomvaluebetweenlowerand*//*upperboundsofthisvariable*/〃變異函數(shù)：被該函數(shù)選中后會使得某一變量被一個隨機的值所取代voidmutate(void){inti,j;doubleIbound,hbound;doublex;for(i=0;i<POPSIZE;i++)for(j=0;j<NVARS;j++){x=rand()%1000/1000.0;if(x<PMUTATION){/*findtheboundsonthevariabletobemutated確定*/Ibound=population[i].lower[j];hbound=population[i].upper[j];population[i].gene[j]=randval(lbound,hbound);/*Reportfunction:Reportsprogressofthesimulation.Data*//*dumpedintotheoutputfileareseparatedbycommas*/voidreport(void){inti;doublebest_val;/*bestpopulationfitness最佳種群適應度*/doubleavg;/*avgpopulationfitness平均種群適應度*/doublestddev;/*std.deviationofpopulationfitness*/doublesum_square;/*sumofsquareforstd.calc各個個體平方之和*/doublesquare_sum;/*squareofsumforstd.calc平均值的平方乘個數(shù)*/doublesum;/*totalpopulationfitness所有種群適應度之和*/sum=0.0;sum_square=0.0;for(i=0;i<POPSIZE;i++){sum+=population[i].fitness;sum_square+=population[i].fitness*population[i].fitness;}avg=sum/(double)POPSIZE;square_sum