def select_stars(magnitude, constellation=None, ra_range=None, dec_range=None):
"""
Select a set of stars brighter than the given magnitude, based on coordinate range and/or constellation membership.
Args:
magnitude (float): The maximum magnitude to include
constellation (string): The constellation name; if given, only stars from that constellation are returned
ra_range (tuple): The range (min_ra, max_ra) of right ascension to include, in degrees
dec_range (tuple): The range (min_dec, max_dec) of declination to include, in degrees
Returns:
list: All Star objects in the database matching the criteria
"""
# Build the query
q = """SELECT * FROM skymap_stars WHERE magnitude<={0}""".format(magnitude)
if constellation:
q += """ AND constellation='{0}'""".format(constellation)
if ra_range:
min_ra, max_ra = ra_range
min_ra = ensure_angle_range(min_ra)
max_ra = ensure_angle_range(max_ra)
if min_ra < max_ra:
q += """ AND right_ascension>={0} AND right_ascension<={1}""".format(
min_ra, max_ra
)
elif max_ra < min_ra:
q += """ AND (right_ascension>={0} OR right_ascension<={1})""".format(
min_ra, max_ra
)
else:
# min_ra is equal to max_ra: full circle: no ra limits
pass
if dec_range:
min_dec, max_dec = dec_range
if (
min_dec < -90
or min_dec > 90
or max_dec < -90
or max_dec > 90
or max_dec <= min_dec
):
raise ValueError("Illegal DEC range!")
q += """ AND declination>={0} AND declination<={1}""".format(min_dec, max_dec)
# Order stars from brightest to weakest so displaying them is easier
q += """ ORDER BY magnitude ASC"""
# Execute the query
db = SkyMapDatabase()
rows = db.query(q)
result = [Star(row) for row in rows]
db.close()
return result
def get_label_size(text, fontsize):
db = SkyMapDatabase()
res = db.query_one(
"""SELECT * FROM skymap_labels WHERE label_text="{}" AND fontsize="{}" """
.format(text, fontsize))
db.close()
if res is None:
return None
return res['width'], res['height']
def get_milky_way_curve(id):
db = SkyMapDatabase()
q = "SELECT * FROM milkyway WHERE curve_id={0} ORDER BY id ASC".format(id)
result = db.query(q)
curve = []
for row in result:
curve.append(SphericalPoint(row['ra'], row['dec']))
if curve[0] == curve[-1]:
curve = curve[:-1]
db.close()
return curve
def build_label_database():
db = SkyMapDatabase()
db.drop_table("skymap_labels")
# Create table
db.commit_query("""CREATE TABLE skymap_labels (
label_id INT PRIMARY KEY,
label_text TEXT,
fontsize TEXT,
width REAL,
height REAL)""")
stars = [
Star(r) for r in db.query(
"""SELECT * FROM skymap_stars WHERE proper_name is not null""")
]
p = Point(0, 0)
i = 0
nstars = len(stars)
for n, s in enumerate(stars):
sys.stdout.write("\r{}%".format(int(round(100 * n / float(nstars)))))
sys.stdout.flush()
if not s.proper_name.strip() and not s.identifier_string.strip():
continue
if s.proper_name:
i += 1
if db.query_one(
"""SELECT * FROM skymap_labels WHERE label_text="{}" AND fontsize="{}" """
.format(s.proper_name, "tiny")) is None:
l = Label(p, s.proper_name, fontsize="tiny", render_size=True)
size = l.size
db.commit_query(
"""INSERT INTO skymap_labels VALUES ({}, "{}", "{}", {}, {})"""
.format(i, s.proper_name, "tiny", size[0], size[1]))
if s.identifier_string:
i += 1
if db.query_one(
"""SELECT * FROM skymap_labels WHERE label_text="{}" AND fontsize="{}" """
.format(s.identifier_string, "tiny")) is None:
l = Label(p,
s.identifier_string.strip(),
fontsize="tiny",
render_size=True)
size = l.size
db.commit_query(
"""INSERT INTO skymap_labels VALUES ({}, "{}", "{}", {}, {})"""
.format(i, s.identifier_string, "tiny", size[0], size[1]))
db.close()
def get_constellation_boundaries_for_area(min_longitude,
max_longitude,
min_latitude,
max_latitude,
epoch=REFERENCE_EPOCH):
# Convert longitude to 0-360 values
# TODO: sometimes boundaries cross the map but have no vertices within the map area + margin and are not plotted
min_longitude = ensure_angle_range(min_longitude)
max_longitude = ensure_angle_range(max_longitude)
if max_longitude == min_longitude:
max_longitude += 360
db = SkyMapDatabase()
q = "SELECT * FROM skymap_constellation_boundaries WHERE"
if min_longitude < max_longitude:
q += " ((ra1>={0} AND ra1<={1}".format(min_longitude, max_longitude)
else:
q += " (((ra1>={0} OR ra1<={1})".format(min_longitude, max_longitude)
q += " AND dec1>={0} AND dec1<={1}) OR".format(min_latitude, max_latitude)
if min_longitude < max_longitude:
q += " (ra2>={0} AND ra2<={1}".format(min_longitude, max_longitude)
else:
q += " ((ra2>={0} OR ra2<={1})".format(min_longitude, max_longitude)
q += " AND dec2>={0} AND dec2<={1}))".format(min_latitude, max_latitude)
res = db.query(q)
result = []
pc = PrecessionCalculator(CONST_BOUND_EPOCH, epoch)
for row in res:
p1 = SphericalPoint(row['ra1'], row['dec1'])
p2 = SphericalPoint(row['ra2'], row['dec2'])
e = BoundaryEdge(p1, p2)
e.precess(pc)
result.append(e)
db.close()
return result
def get_constellation_boundaries_for_area(
min_longitude, max_longitude, min_latitude, max_latitude, epoch="J2000.0"
):
# Convert longitude to 0-360 values
# TODO: sometimes boundaries cross the map but have no vertices within the map area + margin and are not plotted
min_longitude = ensure_angle_range(min_longitude)
max_longitude = ensure_angle_range(max_longitude)
if max_longitude == min_longitude:
max_longitude += 360
db = SkyMapDatabase()
q = "SELECT * FROM skymap_constellation_boundaries WHERE"
if min_longitude < max_longitude:
q += " ((ra1>={0} AND ra1<={1}".format(min_longitude, max_longitude)
else:
q += " (((ra1>={0} OR ra1<={1})".format(min_longitude, max_longitude)
q += " AND dec1>={0} AND dec1<={1}) OR".format(min_latitude, max_latitude)
if min_longitude < max_longitude:
q += " (ra2>={0} AND ra2<={1}".format(min_longitude, max_longitude)
else:
q += " ((ra2>={0} OR ra2<={1})".format(min_longitude, max_longitude)
q += " AND dec2>={0} AND dec2<={1}))".format(min_latitude, max_latitude)
res = db.query(q)
result = []
for row in res:
p1 = SkyCoordDeg(row["ra1"], row["dec1"])
p2 = SkyCoordDeg(row["ra2"], row["dec2"])
e = ConstellationBoundaryEdge(p1, p2)
e.precess()
result.append(e)
db.close()
return result
def build_milkyway_database():
print("")
print("Building milky way boundary database")
db = SkyMapDatabase()
# Drop table
db.drop_table("milkyway")
# Create table
db.commit_query("""CREATE TABLE milkyway (
id INT PRIMARY KEY ,
curve_id INT,
ra REAL,
dec REAL
)""")
# Fill table
point_id = 0
curve_id = 0
curve_id, point_id = parse_file(os.path.join(DATA_FOLDER, "milkyway.txt"), db, curve_id, point_id)
curve_id, point_id = parse_file(os.path.join(DATA_FOLDER, "magellanic_clouds.txt"), db, curve_id, point_id)
db.close()
