Consider preallocating for speed

Hello,

i worked out the following code for my college assignment, and i got the error message as "consider for preallocation of speed "for the variable A. I've got this code from https://www.mathworks.com/matlabcentral/fileexchange/47281-fuzzy-traffic-light-controller for reference. i don't know how to clear this message pls help me.

A(i)=ceil(((x(b(i))+(enter/exit)*time);     % warning message

for j=1:A(i)+1
        
    x(b(i))=x(b(i))-exit;      
    xrand=round(abs(rand(1,4)));         
    x=x+xrand;
      if x(b(i))<=0
         x(b(i))=0;
         createfigure2(x,y,figure1);
         pause(exittime)
         break
      end
end

Answer 1

[Ameer Hamza]

It is not an error message; it is just a warning. Pre-allocation helps make the code faster. Read my answer here to get a general idea: https://www.mathworks.com/matlabcentral/answers/614903-for-loop-preallocation-warning