def test_sphere_to_cartesian():
"""Test helper transform function from sphere to cartesian"""
phi, theta, r = (np.pi, np.pi, 1)
# expected value is (1, 0, 0)
z = r * np.sin(phi)
rcos_phi = r * np.cos(phi)
x = rcos_phi * np.cos(theta)
y = rcos_phi * np.sin(theta)
coord = _sphere_to_cartesian(phi, theta, r)
# np.pi is an approx since pi is irrational
assert_almost_equal(coord, (x, y, z), 10)
assert_almost_equal(coord, (1, 0, 0), 10)
def test_sphere_to_cartesian():
"""Test helper transform function from sphere to cartesian"""
phi, theta, r = (np.pi, np.pi, 1)
# expected value is (1, 0, 0)
z = r * np.sin(phi)
rcos_phi = r * np.cos(phi)
x = rcos_phi * np.cos(theta)
y = rcos_phi * np.sin(theta)
coord = _sphere_to_cartesian(phi, theta, r)
# np.pi is an approx since pi is irrational
assert_almost_equal(coord, (x, y, z), 10)
assert_almost_equal(coord, (1, 0, 0), 10)