def neurite_centre_of_mass(neurite):
'''Calculate and return centre of mass of a neurite.'''
centre_of_mass = np.zeros(3)
total_volume = 0
for segment in tree.val_iter(tree.isegment(neurite)):
seg_volume = morphmath.segment_volume(segment)
centre_of_mass = centre_of_mass + seg_volume * segment_centre_of_mass(segment)
total_volume += seg_volume
return centre_of_mass / total_volume
def neurite_centre_of_mass(neurite):
'''Calculate and return centre of mass of a neurite.'''
centre_of_mass = np.zeros(3)
total_volume = 0
for segment in tree.val_iter(tree.isegment(neurite)):
seg_volume = morphmath.segment_volume(segment)
centre_of_mass = centre_of_mass + seg_volume * segment_centre_of_mass(
segment)
total_volume += seg_volume
return centre_of_mass / total_volume
def test_segment_volume():
p0 = Point(0.0, 0.0, 0.0, 3.0, 1)
p1 = Point(2.0, 0.0, 0.0, 3.0, 1)
p2 = Point(4.0, 0.0, 0.0, 3.0, 1)
p3 = Point(4.0, 0.0, 0.0, 6.0, 1)
p4 = Point(1.0, 0.0, 0.0, 3.0, 1)
p5 = Point(4.0, 0.0, 0.0, 3.0, 1)
v01 = segment_volume((p0, p1))
v02 = segment_volume((p0, p2))
v03 = segment_volume((p0, p3))
v04 = segment_volume((p0, p4))
v45 = segment_volume((p4, p5))
v05 = segment_volume((p0, p5))
nt.assert_almost_equal(v01, 56.5486677, places=6)
nt.assert_almost_equal(2*v01, v02)
nt.assert_almost_equal(v03, 263.8937829, places=6)
nt.assert_almost_equal(v45, v05 - v04)
nt.assert_almost_equal(segment_volume((p0, p3)), segment_volume((p3, p0)))
