gnuplot

gnuplot is a portable command-line driven interactive datafile (text or binary) and function plotting utility for UNIX, IBM OS/2, MS Windows, DOS, Apple Mac, VMS, Atari and many other platforms. The software is copyrighted but freely distributed (i.e., you don't have to pay for it). It was originally intended as graphical program which would allow scientists and students to visualize mathematical functions and data. It does this job pretty well, and in addition it serves as non-interactive plotting engine for miscellaneous portable third-party applications, like Octave. Gnuplot is developed and supported since 1986, and having its scripts and commands easy to understand text files, it is time-portable as well.

Gnuplot supports various kinds of plots. In 2D, it can draw line, point, dot, box, histogram graphs or vector fields. In 3D, it supports line, point and dot surfaces, with or without hidden line removal. It supports color or grayscale surfaces and maps, even for non-equidistant and non-rectangular 3D data, otherwise it offers data gridding.

Gnuplot supports many different types of terminals: interactive screen terminals (with mouse and hotkey functionality), pen plotters (like hpgl), printers (including postscript and many color devices), and printings to output file as vectorial pseudo-devices like LaTeX, metafont, pdf, svg, or bitmap png. Gnuplot is easily extensible to include new devices. See home page: http://gnuplot.sourceforge.net/

New

• allow filename completion for system commands and pipes (backport from 5.1)
• option to plot with labels {rotate variable}
• command "set minussign"
• stats command "name" option now accepts "columnheader" or "columnheader(N)"
• command option "set colorbox invert"

Changes

• qt terminal force selection of outline font rather than bitmap font
• post terminal simplex/duplex output depends on PostScript level setting
• improved autoscaling of plot "with boxes"
• qt terminal sets TERM_POLYGON_PIXELS to avoid aliasing artifacts
• all stats and fit commands skip header records if "autotitle columnhead"

Fix

• Do not confuse EOF with 8-bit character 0x177 (E.g. in Cyrillic encodings).
• use blank line rather than 'u' flag in "set table" output of smoothed data
• order dependence of "fillcolor" keyword in plot commands
• svg - better vertical justification of rotated text
• wxt - file export widget correctly handles inactive plots
• qt - preserve leading and trailing whitespace in enhanced text strings
• various bugs affecting matrix data plotted "with image"