Matlab for loop with decreasing loop counter

Question

this for is not working and I can figure out why, can you help me?

for l = (300:1:-1)
    gauss = fspecial('gaussian',[1 round(1+0.15*l)], 0.015*l);
    filter_g(l,:,1) = filter2(gauss, img_d(l,:,1));
    filter_g(l,:,2) = filter2(gauss, img_d(l,:,2));
    filter_g(l,:,3) = filter2(gauss, img_d(l,:,3));

end

Answer 1

The vector (300:1:-1) will evaluate to empty.

Vectors are start:step:end. Thus, you want 300:-1:1