Astro::SLA -- interface to C SLALIB library
==========

This module provides an interface layer to the C version of the SLALIB
library.  From the abstract of the SLALIB manual (written by Pat
Wallace):

   "SLALIB is a library used by writers of positional-astronomy
   applications. Most of the 171 routines are concerned with
   astronomical position and time, but a number have wider
   trigonometrical, numerical or general applications."

This is the README for version 0.93 of Astro::SLA.

Requirements:
-------------

This module requires the C version of the SLALIB library written by
Pat Wallace. It will not work with the Starlink (FORTRAN) version of
SLALIB. Please contact Pat Wallace (ptw@tpsoft.demon.co.uk) for
details of how to obtain the (proprietary) C SLALIB library.

It has been tested with the May 1998 and January 2000 releases of SLALIB.

A C compiler is required - this is an XS module.

Platforms:
----------

   This module has been tested on the following platforms:

   - SPARC Solaris 2.6, Sun CC, perl5.005_03
   - RedHat Linux 6.1, egcs, perl5.005_03
   - RedHat Linux 6.1, egcs, perl5.6.0

Installation:
-------------

 - Edit the Makefile.PL so that the location of the SLA
   library and include files are correct.
 
   In general you will have a libsla.a or a libcsla.a.
   The default is to search for libcsla.a. You will have 
   to change the LIBS entry if you use libsla.a for the C version.
   It is assumed the library is available from /usr/local/lib by default.

   The includes files, slamac.h and slalib.h, should be available
   in the default path. If they are somewhere else the Makefile.PL 
   should be edited to reflect this location. For example,
   change the line
 
     INC => '',

   to

     INC => '-I/home/me/include',

   to pick them up from /home/me/include

Then:

  % perl Makefile.PL
  % make
  % make test
  % make install

Currently there is only one test (converting B1950 to J2000).

Documentation:
--------------

The module provides documentation on how to use the perl interface
to SLALIB. It does not contain information on how to use
SLALIB itself. For more information on SLALIB see:

  http://star-www.rl.ac.uk/star/docs/sun67.htx/sun67.html


Copyright
---------

This module is copyright (C) 1998-2000 Tim Jenness and 
the UK Particle Physics and Astronomy Research Council.  All rights
reserved.  This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself. 

The SLALIB library (C version) is proprietary.  Please contact Patrick
Wallace (ptw@tpsoft.demon.co.uk) if you would like to obtain a copy.

The array handling code was written by Karl Glazebrook.


Changes
-------

See the ChangeLog file for a full list of changes.

Changes in this release (0.93):

  - New utility 'stime' for printing the current time, MJD and LST

  - Add ut2lst_tel command (this was in the docs but not present)

  - Fix bug in slaEg50 (thanks to Chris Phillips)

  - Fix segmentation violation in certain uses of the slaObs
    command on linux.

  - Should now compile cleanly on perl 5.6.0 (now uses PL_na symbols
    in XS layer)

  - slightly improved test suite.

Changes for release 0.92:

  - Export all single precision aliases

  - Export slaDvxv

  - Fix compiler warnings (thanks to Chris Phillips <phillips@jive.nfra.nl>
    for a patch).

Changes for release 0.91:

  - Add DR2S, DR2H and slaEcleq to the export list. 

  - Fix argument order of slaEqgal and slaSupgal
        [patch supplied by Tim Kimball (kimball@stsci.edu)]
 
  - Allow use of single precision names as aliases to double precision 
    commands.
