Why I get this message?

When I run this code:

clear all
clc
close all
d=4; %2; % dimension of the problem
options.ECPSize=2; %50;  % Population size
options.MaxIter=2;%100; % Maximum number of iterations
options.V=[1 2 1]; % Startegy, NPI, Archive size
options.ObjFunction=@myfitness; %@Ackley; % Name of the objective function
options.lb=[0 0 0 0]; %-32*ones(1,d);   % Lower boundaries
options.ub=[10 10 pi pi]; %32*ones(1,d);    % Upper boundaries
options.ProblemSize=length(options.ub);    % Number of the decision variables
options.Display_Flag=1; % Flag for displaying results over iterations
options.run_parallel_index=0; % 1 to run the different runs in parallel
options.run=2; %10; % number of runs
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Till here %%%%%%%%%%%%%%

%--------------------------------------------------------------------------
bestFitnessEvolution=[];
%--------------------------------------------------------------------------
ECPSize = options.ECPSize;
MaxIter = options.MaxIter; % MaxIter: maximum number of iterations
Strategy=options.V(1);
NPI=options.V(2);
archSize=ECPSize/options.V(3);
ObjFunction=options.ObjFunction;
lb=options.lb; % Lower boundaries
ub=options.ub; % Upper boundaries
ProblemSize=options.ProblemSize; % Number of the decision variables
%--------------------------------------------------------------------------
% Initialization
ECP=repmat(lb,ECPSize,1)+rand(ECPSize,ProblemSize).*repmat((ub-lb),ECPSize,1);
F_ECP = feval(ObjFunction,ECP); nEval=ECPSize;
[F_ECP, ind] = sort(F_ECP);
ECP = ECP(ind,:);

if Strategy==1
    pop_fac=2*nchoosek(NPI,2);
elseif Strategy==2
    pop_fac=NPI;
elseif Strategy==3
    pop_fac=2*nchoosek(NPI,2)+NPI;
end

% Main Loop
for iter=1:MaxIter
    pop_arch  = ECP(1:archSize,:);
    F_arch=F_ECP(1:archSize);
    newECP=[];
    newECP1=[];
    newECP2=[];
    
    for i=1:1:ceil(ECPSize/pop_fac)
        % generate beta = Gaussian number, with mean=0.7 and standard
        % deviation=0.1
        Force = normrnd(0.7,0.2);  
        
        SP=sort(randperm(ECPSize,NPI));
        
        SP=SP(1:NPI);
        
        if Strategy==1
            for ii=1:NPI
                for jj=1:NPI
                    S1=ECP(SP(ii),:)+ Force * (ECP(1,:) - ECP(SP(ii),:));
                    if jj<ii
                        S1= S1 + Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        newECP(end+1,:)=S1;
                    elseif jj>ii
                        S1= S1 - Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        newECP(end+1,:)=S1;
                    end
                end
            end
        elseif Strategy==2
            for ii=1:NPI
                S1=ECP(SP(ii),:)+ 0*Force * (ECP(1,:) - ECP(SP(ii),:));
                for jj=1:NPI
                    if jj<ii
                        S1= S1 + Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                    elseif jj>ii
                        S1= S1 - Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                    end
                end
                newECP(end+1,:)=S1;
            end
            
        elseif Strategy==3
            for ii=1:NPI
                S2=ECP(SP(ii),:)+ 1*Force * (ECP(1,:) - ECP(SP(ii),:));
                for jj=1:NPI
                    S1=ECP(SP(ii),:)+ Force * (ECP(1,:) - ECP(SP(ii),:));
                    if jj<ii
                        S1= S1 + Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        S2= S2 + Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        newECP1(end+1,:)=S1;
                    elseif jj>ii
                        S1= S1 - Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        S2= S2 - Force * (ECP(SP(jj),:) - ECP(SP(ii),:));
                        newECP1(end+1,:)=S1;
                    end
                end
                newECP2(end+1,:)=S2;
            end
            newECP=[newECP1; newECP2];
        end
    end
    
    newECP = bound(newECP,lb, ub);
    
    for i1=1:size(newECP,1)
        for j=1:ProblemSize
            r=rand;
            if (r<0.2)
                pos= randi(archSize(1));
                newECP(i1,j)=  pop_arch(pos,j);
            end
        end
    end
    
    
    ECP_All=[pop_arch; newECP];
    F_All=[F_arch feval(ObjFunction,newECP)];
    nEval=nEval+size(newECP,1);
    
    [F_All, index] = sort(F_All);
    ECP_All = ECP_All( index, : );
    ECP = ECP_All (1:ECPSize,:);
    F_ECP = F_All(1:ECPSize);
    
    bestX=ECP(1,:);
    bestFitnessEvolution(iter)=F_ECP(1);
    if options.Display_Flag==1
        fprintf('Iteration N�� is %g Best Fitness is %g\n',iter,F_ECP(1))
    end
end
bestFitness=F_ECP(1);

where myfitness is:

function out=myfitness(b)
  u = [1 2 3 4];
  out1 = u-b;             %needs R2016b or later
  out = sum(out1.^2,2);
end

I get this error:

Error using horzcat
Dimensions of matrices being concatenated are not consistent.
Error in ECPO_v1 (line 124)
    F_All=[F_arch feval(ObjFunction,newECP)]; 

[Mathieu NOE]

hi

have you looked (debug mode) the size of the elements F_arch and feval(ObjFunction,newECP)

[Sadiq Akbar]

Thank you very much dear Mathieu NOE. Yes I have noticed that in the 1st iteration, size of F_arch=2x1 and newECP=2x4, but in 2nd iteration, size of F_arch=1x2 but that of newECP remains the same 2x4.Why this happens? I don't know and due to this this error occurs.But what to do with this to remove this bug?

[Mathieu NOE]

hello

you have to insert some break points where F_arch appears either as input or output

I see that the main loop does involve F_arch in multiple ways and there must be somewhere the explanation why F_arch changes sizes when you iterates :

Going bottom up in your code :

F_arch is concatenated with feval(ObjFunction,newECP) to generate F_All

a few lines after, F_ECP is generated from the above , so depends from F_arch

    F_All=[F_arch feval(ObjFunction,newECP)];
    nEval=nEval+size(newECP,1);
    
    [F_All, index] = sort(F_All);
    ECP_All = ECP_All( index, : );
    ECP = ECP_All (1:ECPSize,:);
    F_ECP = F_All(1:ECPSize);

and at the next iteration, F_arch will be (re)defined from F_ECP :

    % Main Loop
for iter=1:MaxIter
    pop_arch  = ECP(1:archSize,:);
    F_arch=F_ECP(1:archSize);

so test your code carefully line by line (insert breakpoints and check dimensions )

good luck !

Answer 1

[Jan]

Use the debugger to check the sizes of the arrays:

dbstop if error

Type this in the command line and run the code again. When it stops at the error, check:

size(F_arch)
size(feval(ObjFunction,newECP)) 

[Sadiq Akbar]

Thank you very much Jan. I did so and it give the following error:

Error using horzcat

Dimensions of matrices being concatenated are not consistent.

Error in myECPO (line 125)

F_All=[F_arch feval(ObjFunction,newECP)];

[Jan]

Okay. Then check in this line (see my answer):

size(F_arch)
size(feval(ObjFunction,newECP)) 

The error message tells you, that these two arrays cannot be concatenated horizontally. Maybe you have to tramspose one of them?

[Image Analyst]

They must have different number of rows in each of them, like one has 5 rows and the other has a thousand rows or whatever. I assume you think they should have the same number of rows so you need to use normal debugging methods to figure out how one of them got to be a different number of rows than expected.

Debugging in MATLAB | Doug's MATLAB Video Tutorials

[Sadiq Akbar]

Thank you Jan but again it doesn't solve the problem

[Sadiq Akbar]

Thank you very much dear Image Analyst. Yes, I know that they have different sizes as I have told earlier. But the problem is why it is so? Further, what should we do so that this problem is overcome?