Angle¶
-
class
astropy.coordinates.
Angle
[source] [edit on github]¶ Bases:
astropy.units.quantity.SpecificTypeQuantity
One or more angular value(s) with units equivalent to radians or degrees.
An angle can be specified either as an array, scalar, tuple (see below), string,
Quantity
or anotherAngle
.The input parser is flexible and supports a variety of formats:
Angle('10.2345d') Angle(['10.2345d', '-20d']) Angle('1:2:30.43 degrees') Angle('1 2 0 hours') Angle(np.arange(1, 8), unit=u.deg) Angle('1°2′3″') Angle('1d2m3.4s') Angle('-1h2m3s') Angle('-1h2.5m') Angle('-1:2.5', unit=u.deg) Angle((10, 11, 12), unit='hourangle') # (h, m, s) Angle((-1, 2, 3), unit=u.deg) # (d, m, s) Angle(10.2345 * u.deg) Angle(Angle(10.2345 * u.deg))
Parameters: - angle :
array
, scalar,Quantity
,Angle
The angle value. If a tuple, will be interpreted as
(h, m, s)
or(d, m, s)
depending onunit
. If a string, it will be interpreted following the rules described above.If
angle
is a sequence or array of strings, the resulting values will be in the givenunit
, or ifNone
is provided, the unit will be taken from the first given value.- unit :
UnitBase
, str, optional The unit of the value specified for the angle. This may be any string that
Unit
understands, but it is better to give an actual unit object. Must be an angular unit.- dtype :
dtype
, optional See
Quantity
.- copy : bool, optional
See
Quantity
.
Raises: - `~astropy.units.UnitsError`
If a unit is not provided or it is not an angular unit.
Attributes Summary
dms
The angle’s value in degrees, as a named tuple with (d, m, s)
members.hms
The angle’s value in hours, as a named tuple with (h, m, s)
members.hour
The angle’s value in hours (read-only property). signed_dms
The angle’s value in degrees, as a named tuple with (sign, d, m, s)
members.Methods Summary
is_within_bounds
([lower, upper])Check if all angle(s) satisfy lower <= angle < upper
to_string
([unit, decimal, sep, precision, …])A string representation of the angle. wrap_at
(wrap_angle[, inplace])Wrap the Angle
object at the givenwrap_angle
.Attributes Documentation
-
dms
¶ The angle’s value in degrees, as a named tuple with
(d, m, s)
members. (This is a read-only property.)
-
hms
¶ The angle’s value in hours, as a named tuple with
(h, m, s)
members. (This is a read-only property.)
-
hour
¶ The angle’s value in hours (read-only property).
-
signed_dms
¶ The angle’s value in degrees, as a named tuple with
(sign, d, m, s)
members. Thed
,m
,s
are thus always positive, and the sign of the angle is given bysign
. (This is a read-only property.)This is primarily intended for use with
dms
to generate string representations of coordinates that are correct for negative angles.
Methods Documentation
-
is_within_bounds
(lower=None, upper=None)[source] [edit on github]¶ Check if all angle(s) satisfy
lower <= angle < upper
If
lower
is not specified (orNone
) then no lower bounds check is performed. Likewiseupper
can be left unspecified. For example:>>> from astropy.coordinates import Angle >>> import astropy.units as u >>> a = Angle([-20, 150, 350] * u.deg) >>> a.is_within_bounds('0d', '360d') False >>> a.is_within_bounds(None, '360d') True >>> a.is_within_bounds(-30 * u.deg, None) True
Parameters: - lower : str,
Angle
, angularQuantity
,None
Specifies lower bound for checking. This can be any object that can initialize an
Angle
object, e.g.'180d'
,180 * u.deg
, orAngle(180, unit=u.deg)
.- upper : str,
Angle
, angularQuantity
,None
Specifies upper bound for checking. This can be any object that can initialize an
Angle
object, e.g.'180d'
,180 * u.deg
, orAngle(180, unit=u.deg)
.
Returns: - is_within_bounds : bool
True
if all angles satisfylower <= angle < upper
- lower : str,
-
to_string
(unit=None, decimal=False, sep='fromunit', precision=None, alwayssign=False, pad=False, fields=3, format=None)[source] [edit on github]¶ A string representation of the angle.
Parameters: - unit :
UnitBase
, optional Specifies the unit. Must be an angular unit. If not provided, the unit used to initialize the angle will be used.
- decimal : bool, optional
If
True
, a decimal representation will be used, otherwise the returned string will be in sexagesimal form.- sep : str, optional
The separator between numbers in a sexagesimal representation. E.g., if it is ‘:’, the result is
'12:41:11.1241'
. Also accepts 2 or 3 separators. E.g.,sep='hms'
would give the result'12h41m11.1241s'
, or sep=’-:’ would yield'11-21:17.124'
. Alternatively, the special string ‘fromunit’ means ‘dms’ if the unit is degrees, or ‘hms’ if the unit is hours.- precision : int, optional
The level of decimal precision. If
decimal
isTrue
, this is the raw precision, otherwise it gives the precision of the last place of the sexagesimal representation (seconds). IfNone
, or not provided, the number of decimal places is determined by the value, and will be between 0-8 decimal places as required.- alwayssign : bool, optional
If
True
, include the sign no matter what. IfFalse
, only include the sign if it is negative.- pad : bool, optional
If
True
, include leading zeros when needed to ensure a fixed number of characters for sexagesimal representation.- fields : int, optional
Specifies the number of fields to display when outputting sexagesimal notation. For example:
- fields == 1:
'5d'
- fields == 2:
'5d45m'
- fields == 3:
'5d45m32.5s'
By default, all fields are displayed.
- fields == 1:
- format : str, optional
The format of the result. If not provided, an unadorned string is returned. Supported values are:
- ‘latex’: Return a LaTeX-formatted string
- ‘unicode’: Return a string containing non-ASCII unicode characters, such as the degree symbol
Returns: - strrepr : str or array
A string representation of the angle. If the angle is an array, this will be an array with a unicode dtype.
- unit :
-
wrap_at
(wrap_angle, inplace=False)[source] [edit on github]¶ Wrap the
Angle
object at the givenwrap_angle
.This method forces all the angle values to be within a contiguous 360 degree range so that
wrap_angle - 360d <= angle < wrap_angle
. By default a new Angle object is returned, but if theinplace
argument isTrue
then theAngle
object is wrapped in place and nothing is returned.For instance:
>>> from astropy.coordinates import Angle >>> import astropy.units as u >>> a = Angle([-20.0, 150.0, 350.0] * u.deg) >>> a.wrap_at(360 * u.deg).degree # Wrap into range 0 to 360 degrees array([340., 150., 350.]) >>> a.wrap_at('180d', inplace=True) # Wrap into range -180 to 180 degrees >>> a.degree array([-20., 150., -10.])
Parameters: Returns:
- angle :