gnuplot is a command-line program that can generate two- and three-dimensional plots of functions, data, and data fits. The program runs on all major computers and operating systems. It is a program with a fairly long history, dating back to 1986. Despite its name, this software is not part of the GNU Project.
Features
gnuplot can produce output directly on screen, or in many formats of graphics files, including Portable Network Graphics, Encapsulated PostScript, Scalable Vector Graphics, JPEG and many others. It is also capable of producing LaTeX code that can be included directly in LaTeX documents, making use of LaTeX's fonts and powerful formula notation abilities. The program can be used both interactively and in batch mode using scripts. gnuplot can read data in multiple formats, including ability to read data on the fly generated by other programs, create multiple plots on one image, do 2D, 3D, contour plots, parametric equations, supports various linear and non-linear coordinate systems, projections, geographic and time data reading and presentation, box plots of various forms, histograms, labels, and other custom elements on the plot, including shapes, text and images, that can be set manually, computed by script or automatically from input data. gnuplot also provides scripting capabilities, looping, functions, text processing, variables, macros, arbitrary pre-processing of input data, as well ability to perform non-linear multi-dimensional multi-set weighted data fitting. The gnuplot core code is programmed in C. Modular subsystems for output via Qt, wxWidgets, and LaTeX/TikZ/ConTeXt are written in C++ and Lua. The code below creates the graph to the right. set title "Some Math Functions" set xrange set yrange set zeroaxis plot **2, sin, 1/x
The name of this program was originally chosen to avoid conflicts with a program called "newplot", and was originally a compromise between "llamaplot" and "nplot".
Distribution terms
Despite gnuplot's name, it is not named after, part of or related to the GNU Project, nor does it use the GNU General Public License. It was named as part of a compromise by the original authors, punning on gnu and newplot. Official source code to gnuplot is freely redistributable, but modified versions thereof are not. The gnuplot license instead recommends distribution of patches against official releases, optionally accompanied by officially released source code. Binaries may be distributed along with the unmodified source code and any patches applied thereto. Contact information must be supplied with derived works for technical support for the modified software.
Permission to modify the software is granted, but not the right to distribute the complete modified source code. Modifications are to be distributed as patches to the released version.
Despite this restriction, gnuplot is accepted and used by many GNU packages and is widely included in Linux distributions including the stricter ones such as Debian and Fedora. The OSI Open Source Definition and the Debian Free Software Guidelines specifically allow for restrictions on distribution of modified source code, given explicit permission to distribute both patches and source code. Newer gnuplot modules have been contributed under dual-licensing terms, e.g. gnuplot + BSD or gnuplot + GPL.
GUIs and programs that use gnuplot
Several third-party programs have graphical user interfaces that can be used to generate graphs using gnuplot as the plotting engine. These include:
Gnuplot allows you to represent the results in several ways:
By console
Visually on the Web (with output formats like svg, HTML5 ---
Directly in a file : In this case, GNU allows us to export the final images in a wide variety of different formats. Although we can see all the formats that it supports using the help set term command, output formats such as: aifm,cgi, dumb, eps, gif, gnugraph, jpeg, latex, pdf, png, xlib…..
