This is the distribution for PLplot, a scientific plotting package.  PLplot is
relatively small, portable, freely distributable, and is rich enough to
satisfy most users.  It has a wide range of plot types including line (linear,
log), contour, 3D, fill, and almost 1000 characters (including Greek and
mathematical) in its extended font set.  The package is designed to make it
easy to quickly get graphical output; only a handful of function calls is
typically required.  For more advanced use, virtually all aspects of plotting
are configurable. 

The PLplot package is distributable under the terms of the GNU Library General
Public License (LGPL) with some exceptions -- see the file "Copyright" for
full information.  The intent here is to ensure that PLplot continues to
evolve in a positive way, while remaining freely distributable.  Placing the
library under the LGPL enables software developers to use the PLplot library
as an integral part of their product, even a commercial product. 

We welcome suggestions on how to improve this code, especially in the form
of user-contributed additions, enhancements or bug fixes. If PLplot is used
in any published papers, please include an acknowledgment or citation of our
work, which will help us to continue improving PLplot. Also, please remember
that as PLplot is not a commercial product, we cannot be expected to offer
the kind of support that a commercial product may. There is great interest
in extending PLplot and fixing bugs, but the principal authors can only
afford to work on it part time.  Improvements will necessarily focus on
those which help us get our work done.

The PLplot library is written in C, enabling it to run on many platforms
practically without modification.  Fortran programs may use it
transparently; stub routines are provided to handle the C<->Fortran
interface without any modification of the user program.  C programs are
required to include the header file "plplot.h"; see the documentation for
more details.  Programmes written in many other languages can also use the
PLplot library.  The C++, Tcl, Python, Octave, and Yorick (this
front end is maintained independently, see yplot.sf.net) front ends to PLplot
are mature, the Java front end is almost there (most examples work), and
the Perl front end is still quite incomplete.

The main documentation for PLplot is available on-line at
http://plplot.sourceforge.net/resources/docbook-manual/.  This is generated
from DocBook source within the doc/docbook tree. In some cases the
documentation lags actual improvements to the code, so consult "NEWS" to see
a list of recent changes.

At present, PLplot is actively supported on the following systems:

	Unix:	Most Unix systems including recent good reports on
		AIX 		(IBM)
		IRIX		(Silicon Graphics)
		Linux		(various)
		OSF/1		(DEC/Compaq)
		OS X		(Macintosh, one good report)
		SCO		(SCO)
		SunOS		(Sun)

	MS-DOS (DJGPP)
	Windows (95?, 98, NT, 2000)

Many different output device drivers are available, including postscript,
tektronix, HP laserjet, HP pen plotters, XFig, xterm, X-windows, and a
portable metafile format, among others.  The Tk driver under Unix/X provides
a full user interface based on the plframe plotting widget (see below).  The
metafile renderer (plrender) supports all of the standard operations as well
as seeking operations (backward, forward, or to any specified page) when
interactively viewing metafile output.

Part of the PLplot package is a Tcl-based interpreter (pltcl).  This
program allows interactive plotting using the Tcl script language with
plotting extensions.

Also part of PLplot is a Tk-based plotting widget, called a plframe.  This
widget is based on the Tk frame widget, and supports a variety of user
options such as zoom, scrolls, save to a variety of devices, print,
resize, page layout, orientation change, and palette manipulation.  Direct
plotting to the widget may be done by calls to the underlying library
using either C or Fortran bindings, and a large number of operations can
be interpreted directly (in Tcl) by the widget.

For more information on how to get or use PLplot on your system, see:
 - appendices to the PLplot manual
 - system-specific documentation in the appropriate sys/<system> directory.

SourceForge provides most of the facilities currently used by PLplot.  The
PLplot homepage can be found at http://plplot.sf.net.  The PLplot project
page can be found at http://sourceforge.net/projects/plplot where you can
find source tarballs and rpm's for several Linux distributions and browse
the CVS tree and the archives of our mailing lists.  These mailing lists
include plplot-general (announcements and user questions/answers),
plplot-devel (discussions of PLplot development), and plplot-cvs
(notification of CVS changes).


CREDITS
-------

PLplot is the result of the effort of many people, so it is impractical to
list all the contributors.  Those currently supporting and otherwise
responsible for the package in its present form are given in the AUTHORS
file.
