Reading FITS Files

Introduction

Most of the numerical SDSS-III data is stored in the form of FITS files. These files can contain both images and binary data tables in a well-defined format. FITS files can be read and written with many programming languages, but the most common ones used by SDSS-III are IDL and Python.

IDL

The Goddard utilities contain tools for reading and writing FITS files. The most commonly used functions are mrdfits and mwrfits. The Goddard utilities are included in the idlutils package, which also contains additional programs for manipulating FITS files.

Python

The PyFITS package handles the reading and writing of FITS files in Python. Version 2.4.0 or later is strongly recommended, since this version now correctly reads and writes FITS checksum headers.