% create a grey scale ramp image and show it

wDeg = 1;  %size of image (in degrees)
nPix = 200;  %resolution of image (pixels);
[greyramp_im,y] = meshgrid(linspace(-wDeg/2,wDeg/2,nPix+1));
greyramp_im = x(1:end-1,1:end-1);

figure(1)
clf
imagesc(greyramp_im);
axis equal
axis off
colormap(gray);