@tom Hey guys,
Thank you very much for this wonderful book!
Could you please explain these lines in util.py:
def irc2xyz(coord_irc, origin_xyz, vxSize_xyz, direction_a):
    cri_a = np.array(coord_irc)[::-1]

cri_a should have dimensions c and i swapped compared to coord_irc, right? But  does [::-1] really swap dimensions? Or is it just reversing data along the first dimension?