Building a matrix using while loops? (MATLAB)

by mikeph
Tags: building, loops, matlab, matrix
 P: 1,212 Hello Here is my code: i = 1; j = 1; S = zeros(11,11); while i < 12 while j < 12 S(i,j) = Test1(a(i,j),b(i,j),c(i,j)); j = j + 1; end i = i + 1; end a,b,c are all 11x11 matrices and Test1 is a function m-file which outputs a number. (I have tested it for all the values that a(i,j), b(i,j) and c(i,j) take). My code is only calculating the first row of S, ie. S(2,1) = 0 still. I don't know why the program is ending without adding 1 onto i and repeating the loop, I can only imagine the "while" loop is the wrong way of going about this? Thanks for any help, Mike
 Mentor P: 21,256 A better choice is a for loop for each of your loops. for i=1:11 for j = 1:11 %% loop body end end You can do what you're doing with while loops, but they are in a sense more primitive control structures, so you have to do more of the work in your code. I think what might be happening is that after the inner loop has gone through a complete set of iterations, and i is now 2, you still have the last value of j (=12) in your inner loop. A fix for this problem might be like so: while i < 12 j = 1 %% added this line while j < 12 S(i,j) = Test1(a(i,j),b(i,j),c(i,j)); j = j + 1; end i = i + 1; end