Subscript indices must either be real positive integers or logicals.

I get this error with matlab: "Subscript indices must either be real positive integers or logicals."

I can't understand why

the picture i use : href="http://www.freeimagehosting.net/5byoo"<img src="http://www.freeimagehosting.net/t/5byoo.jpg"></a>

x = imread('eye.jpg'); abu = rgb2gray(x); x2 = double(abu); thres_new = 150; thres = 0; [r c] = size(x2); while (thres ~= thres_new) m1=0; m2=0; thres = thres_new; for i=1:r for i=1:c if(x2(i,j) >= thres) m1=m1+x2(i,j); else m2=m2+x2(i,j); end end end [x y] = size(find(x2 >= thres)); m1_len = x; [x y] = size(find(x2 < thres)); m2_len = x; avg = ((m1/m1_len) + (m2/m2_len))/2; thres_new = avg; end

[Jan]

Please format your code properly. Currently it is not readable. When you search for it, you will find the corresponding instructions fast.