def test_default_observer_transform_hcc():
center = frames.HeliographicStonyhurst(0 * u.deg,
0 * u.deg,
obstime="2017-07-11 15:00")
hpc = center.transform_to(frames.Heliocentric(obstime="2017-07-11 15:00"))
assert_quantity_allclose(hpc.y, -48471.1283979 * u.km)
def semi_circular_loop(length: u.m, theta0: u.deg = 0 * u.deg):
"""
Return a Heliographic Stonyhurst coordinate object with points of a semi circular loop in it.
"""
r_sun = const.R_sun
def r_2_func(x):
return np.arccos(0.5 * x / r_sun.to(u.cm).value) - np.pi + length.to(
u.cm).value / 2. / x
r_2 = scipy.optimize.bisect(r_2_func,
length.to(u.cm).value / (2 * np.pi),
length.to(u.cm).value / np.pi) * u.cm
alpha = np.arccos(0.5 * (r_2 / r_sun).decompose())
phi = np.linspace(-np.pi * u.rad + alpha, np.pi * u.rad - alpha, 2000)
# Quadratic formula to find r
a = 1.
b = -2 * (r_sun.to(u.cm) * np.cos(phi.to(u.radian)))
c = r_sun.to(u.cm)**2 - r_2.to(u.cm)**2
r = (-b + np.sqrt(b**2 - 4 * a * c)) / 2 / a
# Choose only points above the surface
i_r = np.where(r > r_sun)
r = r[i_r]
phi = phi[i_r]
hcc_frame = frames.Heliocentric(
observer=SkyCoord(lon=0 * u.deg,
lat=theta0,
radius=r_sun,
frame='heliographic_stonyhurst'))
return SkyCoord(x=r.to(u.cm) * np.sin(phi.to(u.radian)),
y=u.Quantity(r.shape[0] * [0 * u.cm]),
z=r.to(u.cm) * np.cos(phi.to(u.radian)),
frame=hcc_frame).transform_to('heliographic_stonyhurst')
def test_great_arc_calculable(start, end):
c = SkyCoord(start[0]*u.degree, start[1]*u.degree, frame=frames.HeliographicStonyhurst,
observer=frames.HeliographicStonyhurst(0*u.deg, 0*u.deg, 1*u.AU))
d = SkyCoord(end[0]*u.degree, end[1]*u.degree, frame=frames.HeliographicStonyhurst,
observer=frames.HeliographicStonyhurst(0*u.deg, 0*u.deg, 1*u.AU))
gc = GreatArc(c, d)
c_trans = c.transform_to(frames.Heliocentric)
assert gc.start.x == c_trans.x
assert gc.start.y == c_trans.y
assert gc.start.z == c_trans.z
assert gc.start.observer.lat == 0*u.deg
assert gc.start.observer.lon == 0*u.deg
assert gc.start.observer.radius == 1 * u.AU
d_trans = d.transform_to(frames.Heliocentric(observer=c.observer))
assert gc.end.x == d_trans.x
assert gc.end.y == d_trans.y
assert gc.end.z == d_trans.z
assert gc.end.observer.lat == 0*u.deg
assert gc.end.observer.lon == 0*u.deg
assert gc.end.observer.radius == 1 * u.AU
np.testing.assert_almost_equal(gc.inner_angle.to('deg').value, 45.0)
np.testing.assert_almost_equal(gc.radius.to('km').value, sun.constants.radius.to('km').value)
np.testing.assert_almost_equal(gc.distance.to(
'km').value, sun.constants.radius.to('km').value * 2 * np.pi/8, decimal=1)
def rot_hcc():
return (f.Heliocentric,
RotatedSunFrame(x=1 * u.AU,
y=2 * u.AU,
z=3 * u.AU,
base=f.Heliocentric(observer='earth',
obstime='2001-01-01'),
duration=4 * u.day))
def test_hcc_observer_version(tmpdir):
"""
This test verifies that the heliocentric frame has an upto date list of
the HGS schema versions by ensuring that a HPC frame with a instantiated
HGS frame as the observer round trips correctly.
"""
time = "2021-10-13T11:08"
obs = frames.HeliographicStonyhurst(0*u.deg, 0*u.deg, 1*u.AU, obstime=time)
coord = frames.Heliocentric(1*u.Mm, 1*u.Mm, 1*u.Mm, obstime=time, observer=obs)
assert_round_trip_frame(coord)
def semi_circular_loop(length: u.cm, latitude: u.deg = 0 * u.deg):
"""
Return HGS coordinates for a semi-circular loop
"""
angles = np.linspace(0, 1, 1000) * np.pi * u.rad
z = length / np.pi * np.sin(angles)
x = length / np.pi * np.cos(angles)
hcc_frame = frames.Heliocentric(observer=frames.HeliographicStonyhurst(
lon=0 * u.deg, lat=latitude, radius=constants.au))
return SkyCoord(x=x,
y=np.zeros_like(x),
z=z + constants.radius,
frame=hcc_frame)
def test_great_arc_different_observer(aia171_test_map):
a = SkyCoord(600 * u.arcsec,
-600 * u.arcsec,
frame=aia171_test_map.coordinate_frame)
observer = SkyCoord(-10.0 * u.deg,
83 * u.deg,
radius=0.9 * u.au,
frame=frames.HeliographicStonyhurst,
obstime=aia171_test_map.date)
b = SkyCoord(400 * u.arcsec,
600 * u.arcsec,
observer=observer,
frame=frames.Helioprojective)
# Test that the input observers are indeed different
assert a.observer.lon != b.observer.lon
assert a.observer.lat != b.observer.lat
assert a.observer.radius != b.observer.radius
# Create the great arc
gc = GreatArc(a, b)
# The start and end points stored internally are Heliocentric
start = gc.start
assert isinstance(start.frame, frames.Heliocentric)
end = gc.end
assert isinstance(end.frame, frames.Heliocentric)
# The start and end points stored internally have the same observer
assert start.observer.lon == end.observer.lon
assert start.observer.lat == end.observer.lat
assert start.observer.radius == end.observer.radius
# The start point stored internally has the Heliocentric coordinates of the initial coordinate passed in.
a2h = a.transform_to(frames.Heliocentric)
assert start.x == a2h.x
assert start.y == a2h.y
assert start.z == a2h.z
# The end point stored internally has the Heliocentric coordinates of the initial coordinate passed in.
b2h = b.transform_to(
frames.Heliocentric(observer=aia171_test_map.observer_coordinate))
# Missing an dp on b2h compared to end (TODO BUG?)
np.testing.assert_almost_equal(end.x.value, b2h.x.value)
np.testing.assert_almost_equal(end.y.value, b2h.y.value)
np.testing.assert_almost_equal(end.z.value, b2h.z.value)
def test_obstime_hack():
"""
Test that the obstime can be updated in place, this is used in the transform pipeline.
"""
h = frames.Heliocentric(observer="earth")
obstime = "2011-01-01"
h._obstime = obstime
assert isinstance(h.observer, frames.HeliographicStonyhurst)
earth = get_earth(obstime)
obs = h._observer
assert isinstance(obs, HeliographicStonyhurst)
assert_quantity_allclose(obs.lon, earth.lon)
assert_quantity_allclose(obs.lat, earth.lat)
assert_quantity_allclose(obs.radius, earth.radius)
def semi_circular_loop(length: u.m, latitude: u.deg = 0 * u.deg):
"""
Return a Heliographic Stonyhurst coordinate object with points of a semi circular loop in it.
"""
r_sun = constants.radius
def r_2_func(x):
return np.arccos(0.5 * x / r_sun.to(u.cm).value) - np.pi + length.to(
u.cm).value / 2. / x
# Find the loop radius corresponding to the loop length
r_2 = scipy.optimize.bisect(r_2_func,
length.to(u.cm).value / (2 * np.pi),
length.to(u.cm).value / np.pi) * u.cm
alpha = np.arccos(0.5 * (r_2 / r_sun))
phi = np.linspace(-np.pi * u.rad + alpha, np.pi * u.rad - alpha, 2000)
hcc_frame = frames.Heliocentric(observer=frames.HeliographicStonyhurst(
lon=0 * u.deg, lat=latitude, radius=1 * u.AU))
return SkyCoord(x=r_2 * np.sin(phi),
y=0 * u.cm,
z=r_2 * np.cos(phi) + r_sun,
frame=hcc_frame).transform_to('heliographic_stonyhurst')
def test_default_hcc_observer():
h = frames.Heliocentric()
assert h.observer is None
h = frames.Heliocentric(observer="mars")
assert h.observer == "mars"
def behind_the_plane_of_the_sun(self):
"""
Returns True if the body is behind the plane of the Sun.
"""
return (self.body.transform_to(frames.Heliocentric(observer=self.observer))).z.value < 0
def test_great_arc_coordinates(points_requested, points_expected, first_point,
last_point, last_inner_angle, last_distance,
aia171_test_map):
coordinate_frame = aia171_test_map.coordinate_frame
a = SkyCoord(600 * u.arcsec, -600 * u.arcsec, frame=coordinate_frame)
b = SkyCoord(-100 * u.arcsec, 800 * u.arcsec, frame=coordinate_frame)
gc = GreatArc(a, b, points=points_requested)
coordinates = gc.coordinates()
inner_angles = gc.inner_angles()
distances = gc.distances()
# Ensure a GreatArc object is returned
assert isinstance(gc, GreatArc)
# Test the properties of the GreatArc object
a_trans = a.transform_to(frames.Heliocentric)
assert gc.start.x == a_trans.x
assert gc.start.y == a_trans.y
assert gc.start.z == a_trans.z
b_trans = b.transform_to(frames.Heliocentric(observer=a.observer))
assert gc.end.x == b_trans.x
assert gc.end.y == b_trans.y
assert gc.end.z == b_trans.z
assert gc.distance_unit == u.m
assert gc.observer == a.observer
assert gc.center.x == 0 * u.m
assert gc.center.y == 0 * u.m
assert gc.center.z == 0 * u.m
assert u.allclose(
gc.start_cartesian * u.m,
np.asarray([428721.0913539, -428722.9051924, 341776.0910214]) * u.km)
assert u.allclose(
gc.end_cartesian * u.m,
np.asarray([-71429.5229381, 571439.071248, 390859.5797815]) * u.km)
assert u.allclose(gc.center_cartesian * u.m, np.asarray([0, 0, 0]) * u.km)
assert u.allclose(
gc.v1 * u.m,
np.asarray([428721.0913539, -428722.9051924, 341776.0910214]) * u.km)
assert u.allclose(gc._r, 696000000.0015007)
assert u.allclose(
gc.v2 * u.m,
np.asarray([-71429.5229381, 571439.071248, 390859.5797815]) * u.km)
assert u.allclose(
gc.v3 * u.m,
np.asarray([56761.6265851, 466230.7005856, 513637.0815867]) * u.km)
# Inner angle
assert gc.inner_angle.unit == u.rad
np.testing.assert_almost_equal(gc.inner_angle.value, 1.8683580432741789)
# Distance
assert gc.distance.unit == u.m
np.testing.assert_approx_equal(gc.distance.value, 1300377198.1299164)
# Radius of the sphere
assert gc.radius.unit == u.m
assert u.isclose(gc.radius.value * u.m, 696000.000001501 * u.km)
# Test the calculation of the SkyCoords
# Coordinates method
# Number of points
assert len(coordinates) == points_expected
# Start and end coordinates
np.testing.assert_almost_equal(coordinates[0].Tx.value, first_point[0])
np.testing.assert_almost_equal(coordinates[0].Ty.value, first_point[1])
np.testing.assert_almost_equal(coordinates[-1].Tx.value, last_point[0])
np.testing.assert_almost_equal(coordinates[-1].Ty.value, last_point[1])
# Inner angles method
# Inner angles
assert len(inner_angles) == points_expected
np.testing.assert_almost_equal(inner_angles[-1].value, last_inner_angle)
# Distances method
assert len(distances) == points_expected
assert u.isclose(distances[-1].value * u.m, last_distance * u.km)
