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NAME

Astro::Aladin - Perl class giving access to images and catalogues

SYNOPSIS

  my $aladin = new Astro::Aladin();
  
  my $aladin = new Astro::Aladin( RA     => $ra, 
                                  Dec    => $dec, 
                                  Radius => $radius );

An instance my be created using the default constructor, or using one that defines an R.A., Dec and Radius for future queries.

DESCRIPTION

This module gives a high level interface to images and catalogues available using the CDS Aladin Application. It sits ontop of the Astro::Aladin::LowLevel module which drives Aladin directly through an anonymous pipe. You should use this module for access to resources rather than the lower level.

REVISION

$Id: Aladin.pm,v 1.3 2003/02/26 19:21:37 aa Exp $

METHODS

Constructor

new

Create a new instance from a hash of options

  $aladin = new Astro::Aladin( %options );

returns a reference to an Aladin object.

Accessor Methods

RA

Return (or set) the current target R.A. defined for future Aladin queries

   $ra = $aladin->ra();
   $aladin->ra( $ra );

where $ra should be a string of the form "HH MM SS.SS", e.g. 21 42 42.66

Dec

Return (or set) the current target Declination defined for future Aladin queries

   $dec = $aladin->dec();
   $dss->aladin( $dec );

where $dec should be a string of the form "+-HH MM SS.SS", e.g. +43 35 09.5 or -40 25 67.89

Radius

Return (or set) a default radius (in arcminutes) for future Aladin queries

   $radius = $aladin->radius();
   $aladin->radius( 20 );
Band

Return (or set) a default waveband for future Aladin queries

   $waveband = $aladin->band();
   $aladin->band( $waveband );

this is only really useful for repetative queries using the same catalogue or image server. Valid choices for the waveband are "UKST Blue", "UKST Red", "UKST Infrared", "ESO Red" and "POSS-I Red".

File

Return (or set) a default file name to save retrieved catalogues or images to

   $filename = $aladin->file();
   $aladin->file( $filename );
supercos_catalog

Retrieves a SuperCOSMOS catalogue from Edinburgh using Aladin.

   $filename = $aladin->supercos_catalog( 
                       RA     => $ra, 
                       Dec    => $dec, 
                       Radius => $radius,
                       File   => $catalog_file,
                       Band   => $waveband );
   
   $filename = $aladin->supercos_catalog();
   

where the RA and Dec are in standard sextuple format and the radius is in arc minutes. Valid choices for the waveband are "UKST Blue", "UKST Red", "UKST Infrared", "ESO Red" and "POSS-I Red".

The routine returns the filename of the retrieved catalogue, or undef is there has been an error. It is possiblle that the Aladin retrevial dies without returning results, leaving a corrupt, empty or nonexistant results file. Existance and readability of the returned file should always be checked when calling this method.

General Methods

configure

Configures the object

Configures the object, takes an options hash as an argument

  $aladin->configure( %options);

Does nothing if the array is not supplied.

COPYRIGHT

Copyright (C) 2003 University of Exeter. All Rights Reserved.

This program was written as part of the eSTAR project and is free software; you can redistribute it and/or modify it under the terms of the GNU Public License.

AUTHORS

Alasdair Allan <aa@astro.ex.ac.uk>,