# FunctionTransform¶

class astropy.coordinates.FunctionTransform(func, fromsys, tosys, priority=1, register_graph=None)[source] [edit on github]

A coordinate transformation defined by a function that accepts a coordinate object and returns the transformed coordinate object.

Parameters: func : callable The transformation function. Should have a call signature func(formcoord, toframe). Note that, unlike CoordinateTransform.__call__, toframe is assumed to be of type tosys for this function. fromsys : class The coordinate frame class to start from. tosys : class The coordinate frame class to transform into. priority : number The priority if this transform when finding the shortest coordinate transform path - large numbers are lower priorities. register_graph : A graph to register this transformation with on creation, or None to leave it unregistered. TypeError If func is not callable. ValueError If func cannot accept two arguments.

Methods Summary

 __call__(fromcoord, toframe)

Methods Documentation

__call__(fromcoord, toframe)[source] [edit on github]