UnitSphericalDifferential¶

class astropy.coordinates.UnitSphericalDifferential(d_lon, d_lat=None, copy=True)[source]¶

Differential(s) of points on a unit sphere.

Parameters:

d_lon, d_latQuantity: The longitude and latitude of the differentials.
copybool, optional: If True (default), arrays will be copied. If False, arrays will be references, though possibly broadcast to ensure matching shapes.

Attributes Summary

`attr_classes`
`d_lat`	Component 'd_lat' of the Differential.
`d_lon`	Component 'd_lon' of the Differential.

Methods Summary

`from_cartesian`(other, base)	Convert the differential from 3D rectangular cartesian coordinates to the desired class.
`from_representation`(representation[, base])	Create a new instance of this representation from another one.
`represent_as`(other_class[, base])	Convert coordinates to another representation.
`to_cartesian`(base)	Convert the differential to 3D rectangular cartesian coordinates.
`transform`(matrix, base, transformed_base)	Transform differential using a 3x3 matrix in a Cartesian basis.

Attributes Documentation

attr_classes = {'d_lat': <class 'astropy.units.quantity.Quantity'>, 'd_lon': <class 'astropy.units.quantity.Quantity'>}¶

Methods Documentation

classmethod from_cartesian(other, base)[source]¶

Convert the differential from 3D rectangular cartesian coordinates to the desired class.

Parameters:

other: The object to convert into this differential.
baseBaseRepresentation: The points for which the differentials are to be converted: each of the components is multiplied by its unit vectors and scale factors. Will be converted to cls.base_representation if needed.

Returns:

BaseDifferential subclass instance: A new differential object that is this class’ type.

classmethod from_representation(representation, base=None)[source]¶

Create a new instance of this representation from another one.

Parameters:

representationBaseRepresentation instance: The presentation that should be converted to this class.
baseinstance of cls.base_representation: The base relative to which the differentials will be defined. If the representation is a differential itself, the base will be converted to its base_representation to help convert it.

represent_as(other_class, base=None)[source]¶

Convert coordinates to another representation.

If the instance is of the requested class, it is returned unmodified. By default, conversion is done via cartesian coordinates.

Parameters:

other_classBaseRepresentation subclass: The type of representation to turn the coordinates into.
baseinstance of self.base_representation: Base relative to which the differentials are defined. If the other class is a differential representation, the base will be converted to its base_representation.

to_cartesian(base)[source]¶

Convert the differential to 3D rectangular cartesian coordinates.

Parameters:

baseinstance of self.base_representation: The points for which the differentials are to be converted: each of the components is multiplied by its unit vectors and scale factors.

Returns:

transform(matrix, base, transformed_base)[source]¶

Transform differential using a 3x3 matrix in a Cartesian basis.

This returns a new differential and does not modify the original one.

Parameters:

matrix(3,3) numpy:array_like: A 3x3 (or stack thereof) matrix, such as a rotation matrix.
baseinstance of cls.base_representation: Base relative to which the differentials are defined. If the other class is a differential representation, the base will be converted to its base_representation.
transformed_baseinstance of cls.base_representation: Base relative to which the transformed differentials are defined. If the other class is a differential representation, the base will be converted to its base_representation.