def test_random_salt():
acis_taco.set_random_salt(None)
illum1 = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
illum2 = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
assert not np.all(illum1 == illum2)
acis_taco.set_random_salt(1)
illum1 = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
illum2 = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
assert np.all(illum1 == illum2)
acis_taco.set_random_salt(2)
illum2 = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
assert not np.all(illum1 == illum2)
def dvals(self):
try:
import acis_taco as taco
except ImportError:
import Chandra.taco as taco
if not hasattr(self, '_dvals') and not self.get_cached():
# Collect individual MSIDs for use in calc_earth_vis()
ephem_xyzs = [getattr(self, 'orbitephem0_{}'.format(x))
for x in ('x', 'y', 'z')]
aoattqt_1234s = [getattr(self, 'aoattqt{}'.format(x))
for x in range(1, 5)]
ephems = np.array([x.dvals for x in ephem_xyzs]).transpose()
q_atts = np.array([x.dvals for x in aoattqt_1234s]).transpose()
self._dvals = np.empty(self.model.n_times, dtype=float)
for i, ephem, q_att in zip(count(), ephems, q_atts):
q_norm = np.sqrt(np.sum(q_att ** 2))
if q_norm < 0.9:
print("Bad quaternion", i)
q_att = np.array([0.0, 0.0, 0.0, 1.0])
else:
q_att = q_att / q_norm
_, illums, _ = taco.calc_earth_vis(ephem, q_att)
self._dvals[i] = illums.sum()
self.put_cache()
return self._dvals
def calc_perigee_map(start='2010:114:20:00:00', stop='2010:117:16:00:00', ngrid=50):
# Get orbital ephemeris in requested time range
print('Fetching ephemeris')
objs = ('orbit', 'lunar', 'solar')
axes = ('x', 'y', 'z')
msids = ['{0}ephem0_{1}'.format(obj, axis)
for obj in objs
for axis in axes]
ephems = fetch.MSIDset(msids, start, stop)
times = ephems[msids[0]].times.copy()
n_ephem = len(ephems[msids[0]].vals)
if any(len(ephems[msid].vals) != n_ephem for msid in msids):
raise ValueError('Unexpected mismatch in ephemeris telemetry sampling')
ephem_xyzs = {}
for obj in ('orbit', 'lunar', 'solar'):
msids = ('{0}ephem0_{1}'.format(obj, axis) for axis in axes)
ephem_xyzs[obj] = np.array([ephems[msid].vals for msid in msids])
illum_maps = []
illum_idxs = []
antisun, xs, ys = get_antisun_grid(ngrid)
antisun_pitches, phis = antisun.img2polar(xs, ys)
for i_ephem, ephem_xyz in enumerate(ephem_xyzs['orbit'].transpose()):
# Calculate a grid of attitude vectors centered on the anti-sun line and extending
# from sun-pitch=180 (center) to sun-pitch=45 (edge).
orbit_r = np.sqrt(np.sum(ephem_xyzs['orbit'][:, i_ephem]**2))
if orbit_r > 50000e3:
continue
sun_eci = ephem_xyzs['solar'][:, i_ephem] - ephem_xyzs['orbit'][:, i_ephem]
att_vecs = antisun.img2eci(xs, ys, sun_eci)
ras, decs = Ska.quatutil.eci2radec(att_vecs)
illum_map = np.zeros((ngrid, ngrid), dtype=np.float32)
print(i_ephem, n_ephem, ephem_xyz)
for iy in range(ngrid):
for ix in range(ngrid):
i_vec = iy * ngrid + ix
if antisun_pitches[i_vec] < 135:
ra, dec = ras[i_vec], decs[i_vec]
roll = Ska.Sun.nominal_roll(ra, dec, times[i_ephem])
_, att_illums, _ = acis_taco.calc_earth_vis(ephem_xyz, [ra, dec, roll], max_reflect=5)
illum = sum(att_illums)
else:
illum = 0.0
illum_map[iy, ix] = illum
illum_idxs.append(i_ephem)
illum_maps.append(illum_map)
# debug_here()
return dict(illums=np.array(illum_maps),
illum_idxs=np.array(illum_idxs),
times=times,
antisun=antisun,
ephem_xyzs=ephem_xyzs,
)
def calc_illums(queue, chandra_ecis, att):
"""Calculate the illumination (Earth solid angle) at specified ephemeris
points ``chandra_ecis`` and attitude ``att``. Put the result into the
multiprocess ``queue``.
"""
illums = []
for chandra_eci in chandra_ecis:
vis, illum, rays = acis_taco.calc_earth_vis(chandra_eci, att, max_reflect=5)
illums.append(sum(illum))
queue.put(illums)
def calc_illums(queue, chandra_ecis, att):
"""Calculate the illumination (Earth solid angle) at specified ephemeris
points ``chandra_ecis`` and attitude ``att``. Put the result into the
multiprocess ``queue``.
"""
illums = []
for chandra_eci in chandra_ecis:
vis, illum, rays = acis_taco.calc_earth_vis(chandra_eci,
att,
max_reflect=5)
illums.append(sum(illum))
queue.put(illums)
def make_earth_vis_grids(nside=32, n_reps=1):
from acis_taco import calc_earth_vis, RAD_EARTH, acis_taco
hp = astropy_healpix.HEALPix(nside=nside, order='nested')
npix = astropy_healpix.nside_to_npix(nside)
print(f'npix={npix}')
lons, lats = hp.healpix_to_lonlat(np.arange(npix))
time0 = time.time()
# Allow randomization between altitudes
for i_rep in range(n_reps):
vis_arrays = []
# Randomize the ray-trace points for each rep
acis_taco._RANDOM_SALT = None
acis_taco.SPHERE_XYZ = acis_taco.random_hemisphere(acis_taco.N_SPHERE)
acis_taco.SPHERE_X = acis_taco.SPHERE_XYZ[:, 0].copy()
for i_alt, alt in enumerate(alts):
srs = SphericalRepresentation(lon=lons,
lat=lats,
distance=alt + RAD_EARTH)
xyzs = srs.to_cartesian()
peb_xs = xyzs.x.to_value()
peb_ys = xyzs.y.to_value()
peb_zs = xyzs.z.to_value()
vis = []
for peb_x, peb_y, peb_z in zip(peb_xs, peb_ys, peb_zs):
_, illums, _ = calc_earth_vis(
p_earth_body=[peb_x, peb_y, peb_z])
vis.append(np.sum(illums))
vis = np.array(vis)
vis_arrays.append(vis)
vis_grid = np.vstack(vis_arrays)
if i_alt % 10 == 0:
print(
f'alt={alt / 1000:.2f} km at dt={time.time() - time0:.1f}')
ii = 1
while True:
filename = Path(f'earth_vis_grid_nside{nside}_rep{ii}.npy')
if filename.exists():
ii += 1
continue
else:
print(f'Saving {filename}')
np.save(filename, vis_grid)
break
return vis_grid
def _earth_solid_angle(ds):
# Collect individual MSIDs for use in calc_earth_vis()
ephem_xyzs = [
ds["msids", "orbitephem0_{}".format(x)] for x in "xyz"
]
aoattqt_1234s = [
ds["msids", "aoattqt{}".format(x)] for x in range(1, 5)
]
ephems = np.array([x.value for x in ephem_xyzs]).transpose()
q_atts = np.array([x.value for x in aoattqt_1234s]).transpose()
ret = np.empty(ds["msids", "orbitephem0_x"].shape, dtype=float)
for i, ephem, q_att in zip(count(), ephems, q_atts):
q_norm = np.sqrt(np.sum(q_att**2))
if q_norm < 0.9:
q_att = np.array([0.0, 0.0, 0.0, 1.0])
else:
q_att = q_att / q_norm
_, illums, _ = calc_earth_vis(ephem, q_att)
ret[i] = illums.sum()
return APQuantity(ret, ds.msids["orbitephem0_x"].times, "sr")
def test_illum_regress():
acis_taco.set_random_salt(1)
illum = acis_taco.calc_earth_vis(p_chandra_eci, att)[1]
assert_allclose(illum, illum_gold)
def calc_perigee_map(start='2010:114:20:00:00',
stop='2010:117:16:00:00',
ngrid=50):
# Get orbital ephemeris in requested time range
print('Fetching ephemeris')
objs = ('orbit', 'lunar', 'solar')
axes = ('x', 'y', 'z')
msids = [
'{0}ephem0_{1}'.format(obj, axis) for obj in objs for axis in axes
]
ephems = fetch.MSIDset(msids, start, stop)
times = ephems[msids[0]].times.copy()
n_ephem = len(ephems[msids[0]].vals)
if any(len(ephems[msid].vals) != n_ephem for msid in msids):
raise ValueError('Unexpected mismatch in ephemeris telemetry sampling')
ephem_xyzs = {}
for obj in ('orbit', 'lunar', 'solar'):
msids = ('{0}ephem0_{1}'.format(obj, axis) for axis in axes)
ephem_xyzs[obj] = np.array([ephems[msid].vals for msid in msids])
illum_maps = []
illum_idxs = []
antisun, xs, ys = get_antisun_grid(ngrid)
antisun_pitches, phis = antisun.img2polar(xs, ys)
for i_ephem, ephem_xyz in enumerate(ephem_xyzs['orbit'].transpose()):
# Calculate a grid of attitude vectors centered on the anti-sun line and extending
# from sun-pitch=180 (center) to sun-pitch=45 (edge).
orbit_r = np.sqrt(np.sum(ephem_xyzs['orbit'][:, i_ephem]**2))
if orbit_r > 50000e3:
continue
sun_eci = ephem_xyzs['solar'][:,
i_ephem] - ephem_xyzs['orbit'][:,
i_ephem]
att_vecs = antisun.img2eci(xs, ys, sun_eci)
ras, decs = Ska.quatutil.eci2radec(att_vecs)
illum_map = np.zeros((ngrid, ngrid), dtype=np.float32)
print(i_ephem, n_ephem, ephem_xyz)
for iy in range(ngrid):
for ix in range(ngrid):
i_vec = iy * ngrid + ix
if antisun_pitches[i_vec] < 135:
ra, dec = ras[i_vec], decs[i_vec]
roll = Ska.Sun.nominal_roll(ra, dec, times[i_ephem])
_, att_illums, _ = acis_taco.calc_earth_vis(
ephem_xyz, [ra, dec, roll], max_reflect=5)
illum = sum(att_illums)
else:
illum = 0.0
illum_map[iy, ix] = illum
illum_idxs.append(i_ephem)
illum_maps.append(illum_map)
# debug_here()
return dict(
illums=np.array(illum_maps),
illum_idxs=np.array(illum_idxs),
times=times,
antisun=antisun,
ephem_xyzs=ephem_xyzs,
)