def test_inert_ratio_prnc_simple_2():
c = np.array([[0, 0],
[1, 1],
[2, 2],
[3, 3],
[4, 2],
[5, 1],
[4, 0],
[3, -1],
[2, -2],
[1, -1],
[0, 0]])
raw = ir.get_inert_ratio_raw(c)
prnc = ir.get_inert_ratio_prnc(c)
tilt = ir.get_tilt(c)
assert np.allclose(raw, 1)
assert np.allclose(prnc, 1.5)
assert np.allclose(tilt, np.pi/4)
def test_inert_ratio_prnc_simple_1():
c = np.array([[0, 0],
[0, 1],
[0, 2],
[1, 2],
[2, 2],
[3, 2],
[3, 1],
[3, 0],
[2, 0],
[1, 0],
[0, 0]])
raw = ir.get_inert_ratio_raw(c)
prnc = ir.get_inert_ratio_prnc(c)
tilt = ir.get_tilt(c)
assert np.allclose(raw, 1.5)
assert np.allclose(prnc, 1.5)
assert np.allclose(tilt, 0)
def test_inert_ratio_prnc():
"""Test equivalence of inert_ratio_raw and inert_ratio_prnc"""
t = np.linspace(0, 2*np.pi, 300)
x1 = 1.7 * np.cos(t)
y1 = 1.1 * np.sin(t)
c1 = np.dstack((x1, y1))[0]
phi = np.arctan2(y1, x1)
rho = np.sqrt(x1**2 + y1**2)
for theta in np.linspace(0.1, 2*np.pi, 14): # arbitrary rotation
for pos_x in np.linspace(-5, 20, 8): # arbitrary x shift
for pos_y in np.linspace(-4.6, 17, 4): # arbitrary y shift
x2 = rho * np.cos(phi + theta) + pos_x
y2 = rho * np.sin(phi + theta) + pos_y
c2 = np.dstack((x2, y2))[0]
raw = ir.get_inert_ratio_raw(c1)
prnc = ir.get_inert_ratio_prnc(c2)
assert np.allclose(raw, prnc, rtol=0, atol=1e-10)
))
rr, cc = polygon(pol1[:, 0], pol1[:, 1], img1.shape)
img1[rr, cc] = True
img2 = rotate(np.array(img1, dtype=int), 5, reshape=False)
img2 = img2 > .5
cont1 = contour.get_contour(img1)
cont2 = contour.get_contour(img2)
# convert mask to inertia ratio
# regular inertia ratio
rir1 = inert_ratio.get_inert_ratio_raw(cont1)
rir2 = inert_ratio.get_inert_ratio_raw(cont2)
# principal inertia ratio
pir1 = inert_ratio.get_inert_ratio_prnc(cont1)
pir2 = inert_ratio.get_inert_ratio_prnc(cont2)
fig = plt.figure(figsize=(7, 3))
ax1 = plt.subplot(221, title="rectangle")
ax1.imshow(img1, cmap="gray_r")
ax1.text(.5,
.5,
"inertia ratio: {:.1f}\nprincipal inertia ratio: {:.1f}".format(
rir1, pir1),
transform=ax1.transAxes,
color="w",
va="center",
ha="center")