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    PGPERL        - A GRAPHICS EXTENSION FOR PERL.
    ------        - A MACRO LANGUAGE FOR PGPLOT.

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***Now available for perl5***

INTRODUCTION
------------

'pgperl' is a version of the Perl language which has available
the PGPLOT FORTRAN library, a very popular package for plotting
astronomical data. (As a glance through any issue of ApJ or MNRAS will
confirm.) The details of this involve some complicated C glue routines
but are transparent to the user.

The idea is to provide a command langage for PGPLOT and a more
beautiful alternative to the various (incompatible) flavours of MONGO.
Personally I have always thought that PGPLOT produced far nicer plots
but at greater pain owing to the long compile/link/run cycle of F77 or
C.  Wouldn't it be nice if one could call PGPLOT subroutines directrly
from the elegant perl language?  Five days after reading `Programming
Perl' I found myself at a telescope with little to do, so I hacked out
the basics of `pgperl'.  The rest followed during the odd spare evening
in Cambridge.

Unlike MONGO, perl is a real C-like language with full control
structures, and is very fast and efficient. All the power of perl (and
believe me that is a *lot*) is available to extract data to plot from
multitudes of files in complicated free formats. Using pgperl one has
all the extra functionality of SM (v.t. `SuperMongo') and IMHO the
language is far more robust and elegant.  Unlike the MONGOs pgperl is
free and public domain - though I trust people will communicate
improvements back to me to avoid version explosions.

pgperl is *complete* - all the PGPLOT routines can be used and I have
tested most of them.

I have tried very hard to keep the pgperl calls "obvious" to anybody
who knows PGPLOT and perl. See the notes below for examples of PGPLOT
use from pgperl. I refer people to the excellent reference manuals
available for PGPLOT and perl for complete information.

The current version is 1.0 and is built with PGPLOT v5.0 commands.
There are versions availalable for perl4 (which requires making a new
perl executable linked with pgplot) and perl5 (as a dynamically loadble
perl5 module). If you use pgperl please drop me an email and I can put
you on my mailing list for updates.

See the file LICENSE in the pgperl distribution for copyright/licensing
information and the file pgperl.doc on how to use pgplot from perl.
This is also similar documentation on the pgperl WWW Home Page at:

http://www.ast.cam.ac.uk/~kgb/pgperl.html

Many thanks to Frossie for the original inspiration, and to Larry Wall
and Tim Pearson for providing the excellent ingredients I stuck
together.

enjoy (I hope),

Karl Glazebrook, 
---
kgb@mail.ast.cam.ac.uk              
Institute of Astronomy, Cambridge

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OBTAINING PGPERL
----------------

pgperl can be obtained by anonymous ftp from:

ftp.ast.cam.ac.uk:/pub/kgb/pgperl/     (United Kingdom home site)
linux.nrao.edu:/pub/packages/pgperl/   (United States ftp mirror)


Choose the perl/ or perl5/ directory according to the version you
require.

You then have a choice:

(a) ftp the compressed tar file containing a pre-compiled version, e.g.:

    pgperl1.0_linux.tar.Z
    pgperl1.0_osf1.tar.Z
    pgperl1.0_sol2.tar.Z
    pgperl1.0_sun4.tar.Z

    (pgperl5_*.tar.Z for perl5)

    This has the advantage that you will not need to obtain and build
    PGPLOT as well. Install according to instructions in the
    file BUILDING.

(b) ftp the compressed tar file containing the source only 
    (pgperl1.0_src.tar.Z). Build according to instructions in the
    file BUILDING. You will have to also obtain and build pgplot
    and perl.

See the file CHANGES for a list of recent changes in the current version.

See the file BUILDING in the distribution for a building/installation guide.

See the file README.perl5 for the enhancements/use of the perl5 version.

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                                               Last Modified. 13/June/1995.
