UnitSphericalRepresentation

class astropy.coordinates.UnitSphericalRepresentation(lon, lat, copy=True)

Bases: astropy.coordinates.BaseRepresentation

Representation of points on a unit sphere.

Parameters:

lon, lat : Quantity or str

The longitude and latitude of the point(s), in angular units. The latitude should be between -90 and 90 degrees, and the longitude will be wrapped to an angle between 0 and 360 degrees. These can also be instances of Angle, Longitude, or Latitude.

copy : bool, optional

If True arrays will be copied rather than referenced.

Attributes Summary

attr_classes
lat	The latitude of the point(s).
lon	The longitude of the point(s).
recommended_units

Methods Summary

cross(other)	Cross product of two representations.
from_cartesian(cart)	Converts 3D rectangular cartesian coordinates to spherical polar coordinates.
mean(\*args, \*\*kwargs)	Vector mean.
norm()	Vector norm.
represent_as(other_class)
sum(\*args, \*\*kwargs)	Vector sum.
to_cartesian()	Converts spherical polar coordinates to 3D rectangular cartesian coordinates.

Attributes Documentation

attr_classes = OrderedDict([(u'lon', <class 'astropy.coordinates.angles.Longitude'>), (u'lat', <class 'astropy.coordinates.angles.Latitude'>)])

lat

The latitude of the point(s).

lon

The longitude of the point(s).

recommended_units = {u'lat': Unit("deg"), u'lon': Unit("deg")}

Methods Documentation

cross(other)

Cross product of two representations.

The calculation is done by converting both self and other to CartesianRepresentation, and converting the result back to SphericalRepresentation.

Parameters:

other : representation

The representation to take the cross product with.

Returns:

cross_product : SphericalRepresentation

With vectors perpendicular to both self and other.

classmethod from_cartesian(cart)

Converts 3D rectangular cartesian coordinates to spherical polar coordinates.

mean(*args, **kwargs)

Vector mean.

The representation is converted to cartesian, the means of the x, y, and z components are calculated, and the result is converted to a SphericalRepresentation.

Refer to mean for full documentation of the arguments, noting that axis is the entry in the shape of the representation, and that the out argument cannot be used.

norm()

Vector norm.

The norm is the standard Frobenius norm, i.e., the square root of the sum of the squares of all components with non-angular units, which is always unity for vectors on the unit sphere.

Returns:

norm : Quantity

Dimensionless ones, with the same shape as the representation.

represent_as(other_class)

sum(*args, **kwargs)

Vector sum.

The representation is converted to cartesian, the sums of the x, y, and z components are calculated, and the result is converted to a SphericalRepresentation.

Refer to sum for full documentation of the arguments, noting that axis is the entry in the shape of the representation, and that the out argument cannot be used.

to_cartesian()

Converts spherical polar coordinates to 3D rectangular cartesian coordinates.