I'm trying to subsample the points returned by circle_perimeter and I'm having trouble. Since the points are calculated in octants (and reflected?) it makes walking it somewhat confusing (see below) Does anyone know off hand how I could walk this thing clockwise for example (or produce a sensible subsample of e.g., every other point or every 4th point, etc).

To be a little more concrete:

from skimage.draw import circle_perimeter

rr, cc = circle_perimeter(12, 12, 10)

im = zeros((40,40))

im[rr[::4],cc[::4]] = 1

imshow(im, cmap=cm.gray)

# returns one quadrant of the circle

Still Googling, but I'd appreciate any help =)

Thanks,

Dan