APE26: Removing data storage (representations) from coordinate frames

[jeffjennings]

Coordinate frames in astropy.coordinates currently store metadata used to construct the frame (i.e. for transforming between frames) and may also store coordinate data itself. This duplicates functionality with SkyCoord, which acts as a container for both coordinate data and reference frame information. We propose to change the frame classes such that they only store metadata and never coordinate data. This would make the implementation more modular, remove ambiguity for users from having nearly duplicate functionality with slightly different APIs, and better satisfy the principle of Separation of Concerns.

Authors of this APE (alphabetical): Jeff Jennings @jeffjennings, Adrian Price-Whelan @adrn, Nathaniel Starkman @nstarman, Marten van Kerkwijk @mhvk