CoordinateAttribute

class astropy.coordinates.CoordinateAttribute(frame, default=None, secondary_attribute='')[source]

Bases: astropy.coordinates.Attribute

A frame attribute which is a coordinate object. It can be given as a low-level frame class or a SkyCoord, but will always be converted to the low-level frame class when accessed.

Parameters:
frame : a coordinate frame class

The type of frame this attribute can be

default : object

Default value for the attribute if not provided

secondary_attribute : str

Name of a secondary instance attribute which supplies the value if default is None and no value was supplied during initialization.

Methods Summary

convert_input(self, value) Checks that the input is a SkyCoord with the necessary units (or the special value None).

Methods Documentation

convert_input(self, value)[source]

Checks that the input is a SkyCoord with the necessary units (or the special value None).

Parameters:
value : object

Input value to be converted.

Returns:
out, converted : correctly-typed object, boolean

Tuple consisting of the correctly-typed object and a boolean which indicates if conversion was actually performed.

Raises:
ValueError

If the input is not valid for this attribute.