from mpl_toolkits.mplot3d import Axes3D

figure()
imshow(sphere[:,:,GRID_SIZE>>1], interpolation='none', cmap=cm.gray)
title('2d slice from input sphere')

# Plot large magnitude wavelet coefficients' position in 3D.

figure(figsize=(16,9))
Yh = sphere_t.highpasses
nplts = Yh[-1].shape[3]
nrows = np.ceil(np.sqrt(nplts))
ncols = np.ceil(nplts / nrows)
W = np.max(Yh[-1].shape[:3])
for idx in range(Yh[-1].shape[3]):
    C = np.abs(Yh[-1][:,:,:,idx])
    ax = gcf().add_subplot(nrows, ncols, idx+1, projection='3d')
    ax.set_aspect('equal')
    good = C > 0.2*C.max()
    x,y,z = np.nonzero(good)
    ax.scatter(x, y, z, c=C[good].ravel())
    ax.auto_scale_xyz((0,W), (0,W), (0,W))

tight_layout()