def test_misc():
POS_SPAN = 10
VEL_SPAN = 10
for i in range(100):
# Generate random stars with chron coords between [SPAN, SPAN]
rand_xyz = 2 * POS_SPAN * np.random.rand(3) - POS_SPAN
rand_uvw = 2 * VEL_SPAN * np.random.rand(3) - VEL_SPAN
rand_xyzuvw = np.hstack((rand_xyz, rand_uvw))
rand_galpy = torb.convert_cart2galpycoords(rand_xyzuvw)
rand_epi = eg.convert_galpy2epi(rand_galpy)
galpy_res = eg.convert_epi2galpy(rand_epi)
xyzuvw_res = torb.convert_galpycoords2cart(galpy_res)
try:
# Positions shouldn't vary by more than 3 pc
pos_atol = 2
# Velocities shouldn't vary by more than 0.05 km/s
vel_atol = 0.03
assert np.allclose(rand_xyzuvw[:3], xyzuvw_res[:3], atol=pos_atol)
assert np.allclose(rand_xyzuvw[3:], xyzuvw_res[3:], atol=vel_atol)
# assert np.allclose(rand_galpy, eg.convert_epi2galpy(rand_epi), rtol=rtol)
except AssertionError:
print(i)
import pdb
pdb.set_trace()
def test_evolve_chronspace():
"""
Compare orbits evolved with both galpy and epicyclic, comparing in chron space
"""
time = 50. #Myr
btime = torb.convert_myr2bovytime(time)
chron_start = np.array([0., 0., 10., -2., 0., 0.])
galpy_start = torb.convert_cart2galpycoords(chron_start)
epi_start = eg.convert_galpy2epi(galpy_start)
# Just make sure the starting point can be transformed back and forth
assert np.allclose(galpy_start, eg.convert_epi2galpy(epi_start))
assert np.allclose(
chron_start,
torb.convert_galpycoords2cart(eg.convert_epi2galpy(epi_start)))
epi_end = eg.evolve_epi(epi_start, time)[0]
galpy_end = torb.trace_galpy_orbit(galpy_start,
times=time,
single_age=True)
chron_end = torb.trace_cartesian_orbit(chron_start,
times=time,
single_age=True)
# Chronostar orbit end point, in galpy units
chron_end_gu = torb.convert_cart2galpycoords(chron_end, ts=time)
# This should be exact, because algorithmically it's the same thing.
assert np.allclose(galpy_end, chron_end_gu)
# Epicyclic orbit end point, in chronostar units
epi_end_chron = torb.convert_galpycoords2cart(
eg.convert_epi2galpy(epi_end), ts=btime)
# assert position accurate within 15 pc
# NOTE this is quite large... offset mainly in X. Maybe something to
# investigate.
assert np.allclose(chron_end[:3], epi_end_chron[:3], atol=15.)
# assert velocity accurate within 0.5 km/s
assert np.allclose(chron_end[3:], epi_end_chron[3:], atol=.5)
def test_w_offset():
w_offset = torb.convert_cart2galpycoords([0., 0., 0., 0., 0., 1.])
assert np.allclose(w_offset,
eg.convert_epi2galpy(eg.convert_galpy2epi(w_offset)))
def test_v_offset():
rtol = 1e-4
v_offset = torb.convert_cart2galpycoords([0., 0., 0., 0., 1., 0.])
assert np.allclose(v_offset,
eg.convert_epi2galpy(eg.convert_galpy2epi(v_offset)),
rtol=rtol)
def test_y_offset():
y_offset = torb.convert_cart2galpycoords([0., 10., 0., 0., 0., 0.])
y_res = eg.convert_galpy2epi(y_offset)
assert np.allclose(y_offset,
eg.convert_epi2galpy(eg.convert_galpy2epi(y_offset)))
def test_x_offset():
x_offset = torb.convert_cart2galpycoords([10., 0., 0., 0., 0., 0.])
assert np.allclose(x_offset,
eg.convert_epi2galpy(eg.convert_galpy2epi(x_offset)))