1 Introduction

A harmless necessary cat.
The Merchant of Venice

CAT is the Starlink subroutine library for manipulating astronomical catalogues and similar tabular datasets. This manual provides you with the information necessary to write applications which use it. The manual describes version 9.0 of CAT. CAT is written in Fortran and is part of the Starlink ADAM programming environment. It conforms to all relevant Starlink standards and provides the facilities normally associated with ADAM libraries. A stand-alone version separate from ADAM is possible, but is not described here. Version 9.0 of CAT is available on all the variants of Unix supported by Starlink. The Fortran subroutine interface is identical in all these cases.

CAT provides basic facilities to:

catalogues and tabular datasets. Unlike most similar Starlink libraries it supports catalogues held in various different formats. Currently the formats supported are:

There are idiosyncrasies and limitations associated with each of these formats and they are described in Appendix C.