source: branches/pixel-map-branch/README-beta

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               The Duchamp Source Finder
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Duchamp -- an object finder for spectral-line data cubes
Copyright (C) 2006, Matthew Whiting, ATNF

Duchamp is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

Duchamp is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with Duchamp; if not, write to the Free Software Foundation,
Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA

Correspondence concerning Duchamp may be directed to:
   Internet email: matthew.whiting@atnf.csiro.au
   Postal address: Dr. Matthew Whiting
                   Australia Telescope National Facility, CSIRO
                   PO Box 76
                   Epping NSW 1710
                   AUSTRALIA
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Introduction
------------

Duchamp is a stand-alone program designed to find objects in
astronomical data cubes, particularly spectral-line observations. Its
features include a wavelet-based reconstruction technique for reducing
the noise in the cube (and thereby enhancing detectability of
sources), easy-to-use text-based interface, flexibility to control all
relevant parameters such as detection thresholds, and a useful range
of text- and graphics-based output.

Duchamp works on any FITS image using the CFITSIO package, and uses
Mark Calabretta's WCSLIB library to provide accurate position and
velocity information for all detected sources.


The "Beta" Version
------------------

This distribution of Duchamp, dated 24/01/2007, is known as the beta
version. (The version number when "Duchamp -v" is run is given as
1.1b.). It is more recent than the most recent release (v1.0.7), as
it has several new functions and features. The user should be aware
that these are likely to be undocumented and, while they have been
tested on a limited number of cases, their stability is not assured to
the same level as a proper numbered release.

The beta version is provided more for testing purposes -- if users
want a reliable version of the code that matches the documentation,
please use the latest release available from the webpage given below.


Obtaining and Building Duchamp
------------------------------

The Duchamp web page is at 
http://www.atnf.csiro.au/people/Matthew.Whiting/Duchamp
where you can download a gzipped tar archive of the source code.

Duchamp uses three main external libraries: pgplot, cfitsio (version
2.5 and greater, version 3+ preferred) and wcslib. If you do not have
the libraries, they can be downloaded from the following locations:

PGPlot -- http://www.astro.caltech.edu/~tjp/pgplot/ 
cfitsio -- http://heasarc.gsfc.nasa.gov/docs/software/fitsio/fitsio.html 
wcslib -- http://www.atnf.csiro.au/people/Mark.Calabretta/WCS/index.html

Duchamp can be built on Unix systems by typing (note that the terminal
prompt here is represented by > -- don't type this character!):

 >  ./configure
 >  make
 >  make clean (optional -- to remove the object files from the src
                directory)

This way, configure should find all the necessary libraries, but if
the above-mentioned libraries have been installed in non-standard
locations, you can specify additional directories to look in. There
are separate options for library files (eg. libcpgplot.a) and header
files (eg. cpgplot.h).

For example, suppose wcslib had been locally installed in
/home/mduchamp/wcslib. There will then be two libraries created that
are likely to be in separate subdirectories: C/ and pgsbox/. Each
subdirectory needs to be searched for library and header files, so one
could build Duchamp by typing:

 >  ./configure \
LIBDIRS="/home/mduchamp/wcslib/C /home/mduchamp/wcslib/pgsbox" \
INCDIRS="/home/mduchamp/wcslib/C /home/mduchamp/wcslib/pgsbox"
And then just run make in the usual fashion:
 >  make

There is a script included in the distribution that allows you to make
sure Duchamp is running correctly. It will use a dummy FITS image in
the verification/ directory -- this image has some Gaussian random
noise, with five Gaussian sources present, plus a dummy WCS. The
script runs Duchamp on this image with three different sets of inputs,
and compares to known results, looking for differences and reporting
any. There should be none reported if everything is working
correctly. To run, enter the command

 >  VerifyDuchamp.sh

You can also use the dummy image for your own testing if you like (for
instance, testing different thresholds to get a feel for how the
program works).


Using Duchamp
---------------

There are two possible ways to run Duchamp. The first is:

 >  Duchamp -f image.fits

where image.fits is the data cube to be searched. This method simply
uses the default values of all parameters.

The second method allows some determination of the parameter values by
the user. Type:

 >  Duchamp -p parameterFile 

where parameterFile is a file with the input parameters, including the
name of the cube you want to search. There are two example input files
included with the distribution. The smaller one, InputExample, shows
the typical parameters one might want to set. The large one,
InputComplete, lists all possible parameters that can be entered, and
a brief description of them. To get going quickly, just replace the
"your-file-here" in InputExample with your image name, and type 

 >  Duchamp -p InputExample

A User's Guide in the docs/ directory provides complete
documentation. It comes in both postscript and portable document
format (pdf -- note that this contains hyperlinks). This guide will
provide full descriptions of all parameters, and of all steps in the
execution of Duchamp.

Any questions, please contact me. To report problems or bugs, or to
suggest improvements, please go to the Duchamp Trac wiki site:
http://sourcecode.atnf.csiro.au/cgi-bin/trac_duchamp.cgi/newticket 
and submit a "ticket", or view previously submitted reports.

Author: 
  Matthew Whiting, Australia Telescope National Facility, January 2007
  Matthew.Whiting@csiro.au