The Crates Library: The Redesigned Python Interface for Scripting Languages

Crates is a Python module produced by the Chandra X-ray Center (CXC) that provides a convenient high-level user interface for accessing and manipulating data stored in a variety of formats. Crates is currently utilized by Chandra's plotting, modeling and fitting tools. This paper will highlight the design changes and improvements made to Crates. This version of Crates has been completely rewritten in Python and has been optimized to conserve time and memory resources through lazy initialization. It provides increased functionality for data and metadata manipulation along with better memory management. In addition, Crates will be able to interface with several different backend modules, allowing the user to effortlessly switch between the CXC Data Model (DM), Virtual Observatory (VO), and pyFITS formats.