Description:

The GNU plotting utilities include: (1) GNU libplot, a shared library
for exporting 2-D vector graphics files and for performing vector
graphics animation under the X Window System. Its output file formats
include pseudo-GIF, PNM, Adobe Illustrator, Postscript (editable with
the free 'idraw' drawing editor), Fig (editable with the free g'
drawing editor), PCL 5, HP-GL and HP-GL/2, Tektronix, and GNU metafile
format. Many Postscript, PCL, and Hershey fonts are supported. A
separate class library, 'libplotter', provides a C++ binding to
libplot's functionality. (2) Sample command-line applications 'graph',
'plot', 'tek2plot', 'pic2plot', and 'plotfont', which are built on top
of GNU libplot. 'graph' is a powerful utility for XY plotting, 'plot'
translates GNU metafiles to other formats, 'tek2plot' translates
legacy Tektronix data, 'pic2plot' translates box-and-arrow diagrams in
the pic language, and 'plotfont' plots character maps. (3)
Command-line applications 'spline', 'double', and 'ode', which are
useful in scientific plotting. 'spline' does spline interpolation of
input data of arbitrary dimensionality. It uses cubic splines, splines
under tension, or cubic Bessel interpolation. 'ode' is an interactive
program that can integrate a user-specified system of ordinary
differential equations.