Can anybody tell me what is the mistake in my code?

clc
sss=[];  
for ii=1:20  
    filename=['sdd' num2str(ii) ,'.xls']      
    xx=exist(filename,'file');      
    if xx==0          
        continue  
    else          
        xlfile=['sdd' num2str(ii)]          
        arr=xlsread(xlfile);  
        sss=[sss double(arr(:,1))]          
        [C,I] = min(sss);      
    end   
end

the errors are:

Error using horzcat
Dimensions of matrices being concatenated are not consistent.

Error in Test (line 21)
        sss=[sss double(arr(:,1))]

Answer 1

[Adam]

Take a look at the dimensions of 'arr' after the line:

arr=xlsread(xlfile);

and compare it to sss.

If at some iteration you get a different number of values in arr(:,1) then you will not be able to concatenate it.

Every time round the loop you must have the same length of column vector there in order to concatenate.

We don't have your data though so can't repeat the problem other than by guessing what arr might be.

If you expect that your arr(:,1) will be of different lengths for different files then you will probably need to use a cell array for sss instead.

[Anass Masri]

You are right, the length of column vector is different.

Can you please help me using cell array (find attached the data I'm using)?

[Adam]

You can start with:

sss = cell.empty;

then in your for loop use the following code:

sss = [sss { double(arr(:,1)) }];

in place of your current

sss=[sss double(arr(:,1))];

and that should give you a cell array which you can then extract columns of as e.g

sss{2}