The following list taken from a news posting by Arthur Ferruzzi:
gnuplot ( can act as a filter, and is used by many web CGI's to create graphs )
link = Gnuplot
version 3.6 of gnuplot has GIF output.
mongo/supermongo ( not free ) link = SM
pgplot, link
= PGPLOT
splot,
old but good program. No description, only download. splot.tar.z
jgraph, no description at this time. jgraph Jgraph
home page
psgraph: graphing program with PostScript output; like graph(1), but
more flexible; psgraph
xlispstat ( see below) XLISP-STAT
xgobi XGobi: Dynamic
Graphics for Data Analysis
ACE ( xmgr/xvgr ) link ACE/gr (xmgr, xvgr)ace_gr
xgraph
GLE ( you can get binaries ) graphics layout editor? gle
SAL- Scientific
Data Processing & Visualization - Software Packages -PHYSICA
Algae, formerly Alki Alki Algae Home
yorick ( from LLNL ) link Yorick
scilab
link ScilabScilab Home Page
rlab ( NOT a matlab clone :-) link = RLaB
octave
link =GNU Octave free numerical
analysis and visualization environment, Octave similar to Matlab
mupad ( great package. Basically free. Buy the book ) link = MuPAD
- Multi Processing Algebra Data Tool
R ( gnu clone of "S" statistical language ) link = R
mathematica (
commercial ) symbolic, numeric, graphical Mathematica
matlab ( commercial
) analysis + graphics MATLAB
maple (
commercial) symbolic, numeric, graphical Maple
Others I have come across: