Gray code pattern looks like binary pattern. Is this correct?

Question

I have this following gray code pattern but it looks like binary pattern to me. Please let me know if this is correct or something has to be changed?

n = ceil(log2(py));  T = length(n) ;
gray_pattrn = zeros(2^n,1) ;  gray_pattrn(2) = 1;  T = 2;
for  k = 2:n
   T2 = T+T ;
   gray_pattrn(T+1:T2) = T + flipud(gray_pattrn(1:T)) ;
   T = T2;  
end
mat = transpose(flip(transpose(de2bi(gray_pattrn))));

gray_level = 4; 
patternSeq = transpose(repmat(mat(:, gray_level), 1, 1024));
figure, imagesc(patternSeq); colormap gray;
figure, plot(patternSeq(512,:));

And I got the following images.

Answer 1

Despite the name, Gray code is binary and so what you are getting could very well be correct (I haven't actually checked your code). It's called Gray code because it was invented by Frank Gray, not because it outputs grayscale values (it doesn't).