StaticMatrixTransform

class astropy.coordinates.StaticMatrixTransform(matrix, fromsys, tosys, priority=1, register_graph=None)[source]

Bases: astropy.coordinates.BaseAffineTransform

A coordinate transformation defined as a 3 x 3 cartesian transformation matrix.

This is distinct from DynamicMatrixTransform in that this kind of matrix is independent of frame attributes. That is, it depends only on the class of the frame.

Parameters:
matrix : array-like or callable

A 3 x 3 matrix for transforming 3-vectors. In most cases will be unitary (although this is not strictly required). If a callable, will be called with no arguments to get the matrix.

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 : TransformGraph or None

A graph to register this transformation with on creation, or None to leave it unregistered.

Raises:
ValueError

If the matrix is not 3 x 3

Methods Summary

__call__(self, fromcoord, toframe) Does the actual coordinate transformation from the fromsys class to the tosys class.

Methods Documentation

__call__(self, fromcoord, toframe)[source]

Does the actual coordinate transformation from the fromsys class to the tosys class.

Parameters:
fromcoord : fromsys object

An object of class matching fromsys that is to be transformed.

toframe : object

An object that has the attributes necessary to fully specify the frame. That is, it must have attributes with names that match the keys of the dictionary that tosys.get_frame_attr_names() returns. Typically this is of class tosys, but it might be some other class as long as it has the appropriate attributes.

Returns:
tocoord : tosys object

The new coordinate after the transform has been applied.