V, H = np.mgrid[0:1:100j, 0:1:300j]
S = np.ones_like(V)
HSV = np.dstack((H, S, V))
RGB = hsv_to_rgb(HSV)
pl.imshow(RGB, origin='lower', extent=[0, 360, 0, 1], aspect=150)
pl.xlabel('H')
pl.ylabel('V')
pl.title('$S_{HSV}=1$')
pl.show()
2d hsv color space in matplotlib