% ----------------------------------------------------------------------- %
%% CryStAl for Unconstrained Benchmark Problems
%%
clc;clear all;
%% Get Required Problem Information
ObjFuncName = @(x) Sphere(x); % @CostFunction ;
Var_Number = 100 ; % Number of variables ;
LB = -10 *ones(1,Var_Number) ; % Lower bound of variable ;
UB = 10 *ones(1,Var_Number) ; % Upper bound of variable ;
%% Get Required Algorithm Parameters
MaxIteation = 1000 ; % Maximum number of Iterations ;
Cr_Number = 10 ; % Maximum number of initial Crystals ;
%% Outputs:
% BestCr (Best solution)
% BestFitness (final Best fitness)
% Conv_History (Convergence History Curve)
%% Updating the Size of ProblemParameters
if length(LB)==1
LB=repmat(LB,1,Var_Number);
end
if length(UB)==1
UB=repmat(UB,1,Var_Number);
end
%% Initialization
% Initializing the Position of first probs
for i=1:Cr_Number
Crystal(i,:)=unifrnd(LB,UB);
% Evaluating the initial probs
Fun_eval(i)=feval(ObjFuncName,Crystal(i,:));
end
% The best Crystal
[BestFitness,idbest]=min(Fun_eval);
Crb=Crystal(idbest,:);
% Number of Function Evaluations
Eval_Number=Cr_Number;
%% Search Process
Iter=1;
while Iter<MaxIteation
for i=1:Cr_Number
%% Generate New Crystals
% Main Crystal
Crmain=Crystal(randperm(Cr_Number,1),:);
% Random-selected Crystals
RandNumber=randperm(Cr_Number,1);
RandSelectCrystal=randperm(Cr_Number,RandNumber);
% Mean of randomly-selected Crystals
Fc=mean(Crystal(RandSelectCrystal,:)).*(length(RandSelectCrystal)~=1)...
+Crystal(RandSelectCrystal(1,1),:)*(length(RandSelectCrystal)==1);
% Random numbers (-1,1)
r=2*rand-1; r1=2*rand-1;
r2=2*rand-1; r3=2*rand-1;
% New Crystals
NewCrystal(1,:)=Crystal(i,:)+r*Crmain;
NewCrystal(2,:)=Crystal(i,:)+r1*Crmain+r2*Crb;
NewCrystal(3,:)=Crystal(i,:)+r1*Crmain+r2*Fc;
NewCrystal(4,:)=Crystal(i,:)+r1*Crmain+r2*Crb+r3*Fc;
for i2=1:4
% Checking/Updating the boundary limits for Crystals
NewCrystal(i2,:)=bound(NewCrystal(i2,:),UB,LB);
% Evaluating New Crystals
Fun_evalNew(i2)=feval(ObjFuncName, NewCrystal(i2,:));
% Updating the Crystals
if Fun_evalNew(i2)<Fun_eval(i)
Fun_eval(i)=Fun_evalNew(i2);
Crystal(i,:)=NewCrystal(i2,:);
end
% Updation the Number of Function Evalutions
Eval_Number=Eval_Number+1;
end
end % End of One Iteration
Iter=Iter+1;
% The best Crystal
[BestFitness,idbest]=min(Fun_eval);
Crb=Crystal(idbest,:);
BestCr=Crb;
Conv_History(Iter)=BestFitness;
% Show Iteration Information
disp(['Iteration ' num2str(Iter) ': Best Cost = ' num2str(Conv_History(Iter))]);
end % End of Main Looping
semilogy(Conv_History)
