12 Introduction

 12.1 Copies of the recipe networks

This section presents two extended recipes or case studies of using DX. Both recipes are concerned with importing and visualising three-dimensional ‘cubes’ of observational data. In one case the data were obtained with the James Clerk Maxwell Telescope (JCMT) in Hawaii and in the other with the ROSAT X-ray astronomy satellite. In both cases two of the axes of the cube correspond to a grid of points on the sky (in some projection) and the third axis to a spectrum in frequency or energy. The grids are regularly sampled in all three axes.

This section assumes that you are familiar with the basics of DX. If you are not familiar with DX then you should probably try some of the simple networks in Part I. At the very least you should be follow the ‘Basic Use of DX’ recipe (see Section 4).

12.1 Copies of the recipe networks

Like the simple networks in Part I, the networks and data files referred to in this section can be found on Starlink systems in directory:


and on non-Starlink systems in directory:


The most convenient way to access these files is probably to copy them into your current directory before attempting to read them or load them into DX. The examples in subsequent sections assume that copies of the files are available in your current directory.