%
%?Copyright?（c）?2015?Yarpiz?（www.yarpiz.com）
%?All?rights?reserved.?Please?read?the?“l(fā)icense.txt“?for?license?terms.
%
%?Project?Code:?YPEA107
%?Project?title:?Implementation?of?Differential?Evolution?（DE）?in?MATLAB
%?Publisher:?Yarpiz?（www.yarpiz.com）
%?
%?Developer:?S.?Mostapha?Kalami?Heris?（Member?of?Yarpiz?Team）
%?
%?Contact?Info:?sm.kalami@gmail.com?info@yarpiz.com
%

clc;
clear;
close?all;

%%?Problem?Definition

CostFunction=@（x）?Sphere（x）;????%?Cost?Function

nVar=20;????????????%?Number?of?Decision?Variables

VarSize=[1?nVar];???%?Decision?Variables?Matrix?Size

VarMin=-5;??????????%?Lower?Bound?of?Decision?Variables
VarMax=?5;??????????%?Upper?Bound?of?Decision?Variables

%%?DE?Parameters

MaxIt=1000;??????%?Maximum?Number?of?Iterations

nPop=50;????????%?Population?Size

beta_min=0.2;???%?Lower?Bound?of?Scaling?Factor
beta_max=0.8;???%?Upper?Bound?of?Scaling?Factor

pCR=0.2;????????%?Crossover?Probability

%%?Initialization

empty_individual.Position=[];
empty_individual.Cost=[];

BestSol.Cost=inf;

pop=repmat（empty_individualnPop1）;

for?i=1:nPop

????pop（i）.Position=unifrnd（VarMinVarMaxVarSize）;
????
????pop（i）.Cost=CostFunction（pop（i）.Position）;
????
????if?pop（i）.Cost????????BestSol=pop（i）;
????end
????
end

BestCost=zeros（MaxIt1）;

%%?DE?Main?Loop

for?it=1:MaxIt
????
????for?i=1:nPop
????????
????????x=pop（i）.Position;
????????
????????A=randperm（nPop）;
????????
????????A（A==i）=[];
????????
????????a=A（1）;
????????b=A（2）;
????????c=A（3）;
????????
????????%?Mutation
????????%beta=unifrnd（beta_minbeta_max）;
????????beta=unifrnd（beta_minbeta_maxVarSize）;
????????y=pop（a）.Position+beta.*（pop（b）.Position-pop（c）.Position）;
????????y?=?max（y?VarMin）;
		y?=?min（y?VarMax）;
		
????????%?Crossover
????????z=zeros（size（x））;
????????j0=randi（[1?numel（x）]）;
????????for?j=1:numel（x）
????????????if?j==j0?||?rand<=pCR
????????????????z（j）=y（j）;
????????????else
????????????????z（j）=x（j）;
????????????end
????????end
????????
????????NewSol.Position=z;
????????NewSol.Cost=CostFunction（NewSol.Position）;
????????
????????if?NewSol.Cost????????????pop（i）=NewSol;
????????????
????????????if?pop（i）.Cost???????????????BestSol=pop（i）;
????????????end
????????end
????????
????end
????
????%?Update?Best?Cost
????BestCost（it）=BestSol.Cost;
????
????%?Show?Iteration?Information
????disp（[‘Iteration?‘?num2str（it）?‘:?Best?Cost?=?‘?num2str（BestCost（it））]）;
????
end

%%?Show?Results

figure;
%plot（BestCost）;
semilogy（BestCost?‘LineWidth‘?2）;
xlabel（‘Iteration‘）;
ylabel（‘Best?Cost‘）;
grid?on;

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-05-15?16:15??Differential?Evolution\
?????文件?????????121??2015-09-09?08:24??Differential?Evolution\www.yarpiz.com.url
?????文件????????2702??2015-09-09?08:24??Differential?Evolution\de.m
?????文件?????????398??2015-09-09?08:24??Differential?Evolution\main.m
?????文件?????????440??2015-09-09?08:24??Differential?Evolution\Sphere.m
?????文件????????1350??2015-09-09?08:24??Differential?Evolution\license.txt