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Perturb planetary rvs with inner orbits #407

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6 changes: 6 additions & 0 deletions orbitize/system.py
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Original file line number Diff line number Diff line change
Expand Up @@ -384,6 +384,7 @@ def compute_all_orbits(self, params_arr, epochs=None, comp_rebound=False):

ra_perturb = np.zeros((n_epochs, self.num_secondary_bodies + 1, n_orbits))
dec_perturb = np.zeros((n_epochs, self.num_secondary_bodies + 1, n_orbits))
vz_perturb = np.zeros((n_epochs, self.num_secondary_bodies + 1, n_orbits))

vz = np.zeros((n_epochs, self.num_secondary_bodies + 1, n_orbits))

Expand Down Expand Up @@ -547,6 +548,7 @@ def compute_all_orbits(self, params_arr, epochs=None, comp_rebound=False):
dec_perturb[:, other_body_num, :] -= (
masses[body_num] / mtots[body_num]
) * dec_kepler[:, body_num, :]
vz_perturb[:, other_body_num, :] += vz[:, body_num, :] * 0.0 # perturb on the stellar RV vz0 is already accounted for above when adding vz_i's together. so make these columns 0

else:
ra_perturb[:, other_body_num, :] += (
Expand All @@ -555,9 +557,13 @@ def compute_all_orbits(self, params_arr, epochs=None, comp_rebound=False):
dec_perturb[:, other_body_num, :] += (
masses[body_num] / mtots[body_num]
) * dec_kepler[:, body_num, :]
vz_perturb[:, other_body_num, :] += (
masses[body_num] / mtots[body_num]
) * vz[:, body_num, :]

raoff = ra_kepler + ra_perturb
deoff = dec_kepler + dec_perturb
vz = vz + vz_perturb

if self.fitting_basis == "XYZ":

Expand Down
52 changes: 39 additions & 13 deletions tests/test_multiplanet.py
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Original file line number Diff line number Diff line change
@@ -1,5 +1,6 @@
import os
import numpy as np
import matplotlib.pyplot as plt
import pytest
import astropy.table as table
import orbitize
Expand All @@ -16,15 +17,15 @@ def test_compute_model():
roughly the amplitude we expect.
"""
# generate planet b orbital parameters
b_params = [1, 0, 0, 0, 0, 0]
b_params = [1, 0, np.deg2rad(45), 0, 0, 0]
tau_ref_epoch = 0
mass_b = 0.001 # Msun
m0 = 1 # Msun
plx = 1 # mas

# generate planet c orbital parameters
# at 0.3 au, and starts on the opposite side of the star relative to b
c_params = [0.3, 0, 0, np.pi, 0, 0]
c_params = [0.3, 0, np.deg2rad(45), np.pi, 0, 0]
mass_c = 0.002 # Msun

mtot = m0 + mass_b + mass_c
Expand All @@ -33,7 +34,7 @@ def test_compute_model():
# period_b = np.sqrt(b_params[0] ** 3 / mtot)

epochs = (
np.linspace(0, period_c * 365.25, 5) + tau_ref_epoch
np.linspace(0, period_c * 365.25, 100) + tau_ref_epoch
) # the full period of c, MJD

ra_model, dec_model, vz_model = kepler.calc_orbit(
Expand All @@ -47,6 +48,7 @@ def test_compute_model():
plx,
mtot,
tau_ref_epoch=tau_ref_epoch,
mass_for_Kamp=m0
)

# generate some fake measurements just to feed into system.py to test bookkeeping
Expand All @@ -59,8 +61,10 @@ def test_compute_model():
np.zeros(ra_model.shape),
dec_model,
np.zeros(dec_model.shape),
vz_model,
np.zeros(vz_model.shape),
],
names=["epoch", "object", "raoff", "raoff_err", "decoff", "decoff_err"],
names=["epoch", "object", "raoff", "raoff_err", "decoff", "decoff_err", "rv", "rv_err"],
)
filename = os.path.join(orbitize.DATADIR, "multiplanet_fake_1planettest.csv")
t.write(filename, overwrite=True)
Expand All @@ -81,16 +85,18 @@ def test_compute_model():
# only does planet b measurements
params = np.append(b_params, [plx, mass_b, m0])
radec_1body, _ = sys_1body.compute_model(params)
ra_1body = radec_1body[:, 0]
dec_1body = radec_1body[:, 1]
ra_1body = radec_1body[sys_1body.radec[1], 0]
dec_1body = radec_1body[sys_1body.radec[1], 1]
rv_1body = radec_1body[sys_1body.rv[1], 0]

# model predictions for the 2 body case
# still only generates predictions of b's location, but including the
# perturbation for c
params = np.append(b_params, np.append(c_params, [plx, mass_b, mass_c, m0]))
radec_2body, _ = sys_2body.compute_model(params)
ra_2body = radec_2body[:, 0]
dec_2body = radec_2body[:, 1]
ra_2body = radec_2body[sys_2body.radec[1], 0]
dec_2body = radec_2body[sys_2body.radec[1], 1]
rv_2body = radec_2body[sys_2body.rv[1], 0]

ra_diff = ra_2body - ra_1body
dec_diff = dec_2body - dec_1body
Expand All @@ -103,8 +109,14 @@ def test_compute_model():
mass_c / m0 * c_params[0] * plx, abs=0.01 * mass_c / m0 * b_params[0] * plx
)

# rv_diff = rv_2body - rv_1body
# plt.figure()
# plt.plot(epochs, rv_diff)
# plt.savefig("test_multiplanet.png")

# clean up
os.system("rm {}".format(filename))
# os.system("rm {}".format("test_multiplanet.png"))


def test_fit_selfconsist():
Expand All @@ -113,15 +125,15 @@ def test_fit_selfconsist():
this does not test for correctness.
"""
# generate planet b orbital parameters
b_params = [1, 0, 0, 0, 0, 0.5]
b_params = [1, 0, np.deg2rad(45), 0, 0, 0.5]
tau_ref_epoch = 0
mass_b = 0.001 # Msun
m0 = 1 # Msun
plx = 1 # mas

# generate planet c orbital parameters
# at 0.3 au, and starts on the opposite side of the star relative to b
c_params = [0.3, 0, 0, np.pi, 0, 0.5]
c_params = [0.3, 0, np.deg2rad(45), np.pi, 0, 0.5]
mass_c = 0.002 # Msun

mtot_c = m0 + mass_b + mass_c
Expand Down Expand Up @@ -169,6 +181,7 @@ def test_fit_selfconsist():
# the sign is positive b/c of 2 negative signs cancelling.
ra_model_b += mass_c / m0 * ra_model_c
dec_model_b += mass_c / m0 * dec_model_c
vz_model += mass_c / m0 * vz_model_c

# # perturb c due to b
# ra_model_c += mass_b/m0 * ra_model_b_orig
Expand All @@ -183,12 +196,14 @@ def test_fit_selfconsist():
0.00001 * np.ones(epochs.shape, dtype=int),
dec_model_b,
0.00001 * np.ones(epochs.shape, dtype=int),
vz_model,
0.00001 * np.ones(epochs.shape, dtype=int),
],
names=["epoch", "object", "raoff", "raoff_err", "decoff", "decoff_err"],
names=["epoch", "object", "raoff", "raoff_err", "decoff", "decoff_err", "rv", "rv_err"],
)
# add c
for eps, ra, dec in zip(epochs, ra_model_c, dec_model_c):
t.add_row([eps, 2, ra, 0.000001, dec, 0.000001])
for eps, ra, dec, rv in zip(epochs, ra_model_c, dec_model_c, vz_model_c):
t.add_row([eps, 2, ra, 0.000001, dec, 0.000001, rv, 0.000001])

filename = os.path.join(orbitize.DATADIR, "multiplanet_fake_2planettest.csv")
t.write(filename, overwrite=True)
Expand Down Expand Up @@ -257,6 +272,17 @@ def test_fit_selfconsist():

os.system("rm {}".format(filename))

plt.figure()
plt.scatter(epochs, vz_model)

sol_2body, _ = sys.compute_model(np.median(res.post, axis=0))
rv_2body = sol_2body[sys.rv[1], 0]

plt.plot(epochs, rv_2body)

plt.savefig("test_multiplanet_2.png")
os.system("rm {}".format("test_multiplanet_2.png"))


if __name__ == "__main__":
# test_compute_model()
Expand Down
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