GNU Plotting Utilities The GNU plotting utilities include: (1) Sample command-line applications `graph', `plot', `tek2plot', and `plotfont', which are built on top of the GNU libplot DLL. `graph' is a powerful utility for XY plotting, `plot' translates GNU metafiles to other formats, `tek2plot' translates legacy Tektronix data, and `plotfont' plots character maps. (2) GNU libplot, the underlying DLL for two-dimensional device-independent vector graphics and vector graphics animation under the X Window System. Output formats include X11, Adobe Illustrator, Postscript (editable with the free `idraw' drawing editor), Fig (editable with the free `xfig' drawing editor), PCL 5, HP-GL and HP-GL/2, Tektronix, and GNU metafile format. Many Postscript, PCL, and Hershey fonts are supported. (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.