%
%?Copyright?（c）?2015?Yarpiz?（www.yarpiz.com）
%?All?rights?reserved.?Please?read?the?“license.txt“?for?license?terms.
%
%?Project?Code:?YPEA113
%?Project?title:?Biogeography-based?Optimization?（BBO）?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=5;?????????????%?Number?of?Decision?Variables

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

VarMin=-10;?????????%?Decision?Variables?Lower?Bound
VarMax=?10;?????????%?Decision?Variables?Upper?Bound

%%?BBO?Parameters

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

nPop=50;????????????%?Number?of?Habitats?（Population?Size）

KeepRate=0.2;???????????????????%?Keep?Rate
nKeep=round（KeepRate*nPop）;?????%?Number?of?Kept?Habitats

nNew=nPop-nKeep;????????????????%?Number?of?New?Habitats

%?Migration?Rates
mu=linspace（10nPop）;??????????%?Emmigration?Rates
lambda=1-mu;????????????????????%?Immigration?Rates

alpha=0.9;

pMutation=0.1;

sigma=0.02*（VarMax-VarMin）;

%%?Initialization

%?Empty?Habitat
habitat.Position=[];
habitat.Cost=[];

%?Create?Habitats?Array
pop=repmat（habitatnPop1）;

%?Initialize?Habitats
for?i=1:nPop
????pop（i）.Position=unifrnd（VarMinVarMaxVarSize）;
????pop（i）.Cost=CostFunction（pop（i）.Position）;
end

%?Sort?Population
[~?SortOrder]=sort（[pop.Cost]）;
pop=pop（SortOrder）;

%?Best?Solution?Ever?Found
BestSol=pop（1）;

%?Array?to?Hold?Best?Costs
BestCost=zeros（MaxIt1）;

%%?BBO?Main?Loop

for?it=1:MaxIt
????
????newpop=pop;
????for?i=1:nPop
????????for?k=1:nVar
????????????%?Migration
????????????if?rand<=lambda（i）
????????????????%?Emmigration?Probabilities
????????????????EP=mu;
????????????????EP（i）=0;
????????????????EP=EP/sum（EP）;
????????????????
????????????????%?Select?Source?Habitat
????????????????j=RouletteWheelSelection（EP）;
????????????????
????????????????%?Migration
????????????????newpop（i）.Position（k）=pop（i）.Position（k）?...
????????????????????+alpha*（pop（j）.Position（k）-pop（i）.Position（k））;
????????????????
????????????end
????????????
????????????%?Mutation
????????????if?rand<=pMutation
????????????????newpop（i）.Position（k）=newpop（i）.Position（k）+sigma*randn;
????????????end
????????end
????????
????????%?Apply?Lower?and?Upper?Bound?Limits
????????newpop（i）.Position?=?max（newpop（i）.Position?VarMin）;
????????newpop（i）.Position?=?min（newpop（i）.Position?VarMax）;
????????
????????%?Evaluation
????????newpop（i）.Cost=CostFunction（newpop（i）.Position）;
????end
????
????%?Sort?New?Population
????[~?SortOrder]=sort（[newpop.Cost]）;
????newpop=newpop（SortOrder）;
????
????%?Select?Next?Iteration?Population
????pop=[pop（1:nKeep）
?????????newpop（1:nNew）];
?????
????%?Sort?Population
????[~?SortOrder]=sort（[pop.Cost]）;
????pop

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2015-09-06?16:25??YPEA113?Biogeography-based?Optimization\
?????目錄???????????0??2015-09-06?16:51??YPEA113?Biogeography-based?Optimization\BBO\
?????文件????????3435??2015-10-21?03:56??YPEA113?Biogeography-based?Optimization\BBO\bbo.m
?????文件????????1350??2015-08-23?04:39??YPEA113?Biogeography-based?Optimization\BBO\license.txt
?????文件?????????391??2015-09-06?19:27??YPEA113?Biogeography-based?Optimization\BBO\main.m
?????文件?????????490??2015-09-06?19:27??YPEA113?Biogeography-based?Optimization\BBO\RouletteWheelSelection.m
?????文件?????????432??2015-09-06?19:27??YPEA113?Biogeography-based?Optimization\BBO\Sphere.m
?????文件?????????121??2015-08-23?04:35??YPEA113?Biogeography-based?Optimization\BBO\www.yarpiz.com.url
?????文件????????1350??2015-08-23?04:39??YPEA113?Biogeography-based?Optimization\license.txt
?????文件?????????121??2015-08-23?04:35??YPEA113?Biogeography-based?Optimization\www.yarpiz.com.url