Patches and on-going development work

I am on the gnuplot development team at SourceForge. I keep a web page with current patches and demos of work in progress here.

Serving gnuplot files over the web

gnuplot demo

This is a test of serving up a gnuplot file over the web via mime-type application/gnuplot. If you do not already have gnuplot installed you may obtain a copy of the current release or the CVS development version from SourceForge. Once you have gnuplot installed, then to receive gnuplot files via the web you must insert a line in ~/.mailcap or add the equivalent to the application link menu in your favorite web browser. The simplest case is just to pass the file directly to gnuplot, as in

A more complication version, allowing the user to alter the plot interactively after it appears, could go something like

where webplot is in turn made to be something like
	# This is an executable script called "webplot"
        xterm -geometry 56x10-0+475 -e gnuplot -geometry 640x450-0+0 $1 $2 $3

What else do I need?

The demo above uses only functions internal to gnuplot; it does not plot any data from external files. Clearly to be generally useful as a web tool one would like to be able to have the gnuplot client read data files served up via http. This is in fact possible, at least when gnuplot is running on a system which supports the popen() function (piping input through a shell command). For this to work you need a shell command which can retrieve files over the web. Use the "GET" command from libwww-perl (you need perl installed also). Calls inside gnuplot are then of the form

	plot '< GET'


Here is an example gnuplot file, Mn_scatter.gnu, using this format.
And here is the FORMS INTERFACE which produced it.

Why gnuplot?

I wanted a way to feed graphs via web server, and furthermore I wanted to send them in some format that the user could easily modify after receipt. PostScript fails to meet the latter criterion. I chose gnuplot instead because:

Ethan A Merritt / / Biomolecular Structure Center at UW