How to work with loops?

Hi,

I wrote down this code, however, it gives me the error " Arrays have incompatible sizes for this operation. Error in Code (line 5) row = find(X==i);"

X = [12 12 12 1 1 1 1 1]

for i= unique(X)

row = find(X==i)

for j=[row]

i have some codings here

end

end

Can you please help me? Thanks,

[David Hill]

Runs fine.

X = [12 12 12 1 1 1 1 1];
a=[];
for i= unique(X)
    row = find(X==i);
    for j=row
     a=[a,5];
    end
end
a

a = 1×8

5 5 5 5 5 5 5 5

[ahmad Mohammadi]

Thank you very much. Yes, the problem was X which was:

X = [12; 12; 12; 1; 1; 1; 1; 1];

I did not notice that.