### 10 Summary of applications

CURSA contains the following applications.

xcatview
browse and generate selections from a catalogue (easy-to-use X-windows version with a graphical user interface; see Section 11),
catview
browse and generate selections from a catalogue (command line version; see Section 12),
catheader
list various header information for a catalogue (see Section 13),
catcopy
copy a catalogue (see Section 14),
catsort
sort a catalogue (see Section 15),
catselect
select a subset from a catalogue and save it as a new catalogue (see Section 16),
catcoord
convert catalogue coordinates between celestial coordinate systems (see Section 17),
catchart
plot a basic finding chart from a target list (see Section 18),
catchartrn
customise a target list for prior to plotting it as a finding chart (see Section 18),
catpair
pair two catalogues (see Section 20),
catphotomfit
define photometric transformation coefficients using observations of standard stars (see Section 21),
catphotomtrn
apply photometric transformation coefficients to programme objects (see Section 21),
catphotomlst
list photometric transformation coefficients (see Section 21),
catgrid
bin one, two or three columns from a catalogue into, respectively, a histogram, image or data cube (see Section 22),
catcdsin
convert the text file version of a CDS catalogue to the CURSA STL format (see Section 23),
catgscin
convert a region in the HST Guide Star Catalog to a more convenient format (see Section 24),
catremote
extract a subset from a remote on-line catalogue (see Section 25).

To run any of the applications you simply type its name and answer the ensuing prompts (or, in the case of xcatview dialogue boxes).

xcatview and catview provide essentially the same functionality. However, xcatview is much easier to use and is strongly recommended over catview for casual, interactive examination of a catalogue. It does, however, have to be run from a terminal (or workstation console) capable of supporting X-windows output. The only circumstances where catview is likely to be preferable are if you have a terminal which does not support X output or you are performing repetitive ‘batch’ type operations from a script.

#### 10.1 Copying textual information

The applications which create a new catalogue from an existing one (catcopy, catsort,
catselect, catcoord, catchartrn, catphotomtrn and catgscin) all have a uniform option to control the amount of textual information that they write to the new catalogue.

By default the textual information for the new catalogue is a copy of the textual information for the original catalogue (which is usually what is required). However, options are available to either copy all the details of the original catalogue (including the column and parameter definitions) as textual information for the new catalogue or to copy no textual information to the new catalogue.

These options are invoked by specifying an extra item on the command line when the application is invoked. For example, for catcopy:

• to copy just the textual information from the original catalogue simply give the command name:
catcopy
• to copy the entire description of the input catalogue as textual information in the output catalogue:
catcopy text=all
• to copy no textual information to the output catalogue:
catcopy  text=none

The other applications include exactly the same way option. There must be one or more spaces between the application name and the ‘text=’ item.

#### 10.2 Quiet mode

Most of the applications have a ‘quiet mode’ in which they issue fewer informational and warning messages. The exceptions are catcdsin and catremote, which are Perl scripts rather than conventional applications. The quiet mode suppresses only some informational and warning messages; it does not affect error messages. All the applications which support the quiet mode use the same mechanism to control it. By default the applications are in a ‘verbose’ mode in which they issue informational and warning messages. To switch to quiet mode an additional option is specified when invoking any of the applications which support it, for example:

catcopy  quiet=true

The quiet mode will now remain in effect, not just for the one invocation of catcopy, but for all subsequent invocations of all the applications that support the quiet mode. To revert to verbose mode type, for example:

catchart  quiet=false

The quiet mode can also be set as one of the configuration options of xcatview (see Section 11). Finally, I advise you to use the quiet mode with caution; it is usually better to see the informational and warning messages.

#### 10.3 Extra functionality

CURSA can inter-operate with a number of other packages. These packages provide additional functionality which is not available in CURSA. Perhaps the most extensive and useful is FTOOLS, which is briefly described in Section 10.4, below. Another useful external package is Starbase, which is briefly described in Section 10.5, below.

The image display and analysis tool GAIA[12] reads and writes catalogues in the TST format. Thus, catalogues in this format can be exchanged between CURSA and GAIA. Some limited inter-operability is possible between CURSA and the image processing package KAPPA[5] (see Appendix F) and the image analysis package PISA[13] (see Appendix G).

Finally, CURSA is augmented by the CAT Fortran 77 subroutine library for manipulating catalogues and tables. Using CAT it is straightforward to write your own programs to perform specialised tasks not covered by the more general CURSA applications. Programs written with CAT are fully inter-operable with the standard CURSA applications (in fact the CURSA applications themselves use CAT). CAT is comprehensively documented in SUN/181[10]. A set of simple example programs are included with the CAT library.

#### 10.4 Inter-operability with FTOOLS

FTOOLS is a package for manipulating FITS files, including FITS tables. It comprises a collection of utility programs to create, examine and modify FITS files. FTOOLS contains many useful functions which complement CURSA. It is developed and maintained by the High Energy Astrophysics Science Archive Research Center (HEASARC) at the NASA Goddard Space Flight Center (GSFC) and is in widespread use around the world.

FTOOLS can inter-operate with CURSA. However, clearly, it can only access FITS files, not the other formats accessible to CURSA. If your CURSA catalogues are in one of the other formats you should use catcopy to convert them to FITS tables prior to accessing them with FTOOLS. Also, in order to interpret the celestial coordinates in catalogues CURSA uses specific FITS keywords in the FITS header. Though these keywords are perfectly standard, and FTOOLS will process catalogues containing them, it attaches no special significance to them and will not attempt to interpret the celestial coordinates.

There is a ‘home page’ for FTOOLS at the GSFC. The URL is:

An identical copy is maintained at the LEDAS data archive service of the Department of Physics and Astronomy, University of Leicester. The URL is:

This copy may be more convenient for users in the UK or Europe. The home pages give access to a great deal of useful information about FTOOLS. Copies of the software and its user manual can be retrieved. FTOOLS is available for all the variants of Unix supported by Starlink (and numerous other systems).

#### 10.5 Inter-operability with Starbase

Starbase is a simple relational database management system (RDBMS) for manipulating astronomical catalogues and tables. It was developed by John Roll of the Smithsonian Astrophysical Observatory. It comprises a collection of programs which use standard Unix features and tools. The basic facilities of Starbase are similar to the Unix RDBMS /rdb.

Starbase operates on tables in the Tab-Separated Table (TST) format (see Appendix C.2). It works best on small tables of fewer than 10,000 rows. Starbase can inter-operate with CURSA, though obviously only on catalogues in the TST format. If you wish to use Starbase with catalogues that are not in the TST format then use catcopy (see Section 14) to convert them to this format.