Gnuplot is a command-driven interactive function and data plotting program. The plots are x-y data plots with functions in 2D or x-y-z data plots with surfaces in 3D. The plots can be displayed on the screen for interactive graphical exploration or stored in a file using many common graphical formats. This way the constructed graph can viewed, printed, or saved to be included in a document or web page.

 The official web page for gnuplot is www.gnuplot.info

Where to find gnuplot

  • Where Can I Use gnuplot on Campus?

    Gnuplot version 3.7 is available on Strauss and Mahler in the standard path using the command gnuplot.

  • How Can I Obtain gnuplot for my Personal Computer?

    The current version of gnuplot is 4.4.0, and it is a sourceforge project - see sourceforge.net/projects/gnuplot to download gnuplot. 

Gnuplot instructions

  • Running gnuplot Interactively on Strauss or Mahler.

    At the UNIX prompt (%) type


    The following will appear to begin your command line session:

    G N U P L O T 
    Unix version 3.7
    patchlevel 1 
    last modified Fri Oct 22 18:00:00 BST 1999 
    Copyright(C) 1986 - 1993, 1998, 1999 
    Thomas Williams, Colin Kelley and many others 
    Type `help` to access the on-line reference manual 
    The gnuplot FAQ is available from
    Send comments and requests for help to info-gnuplot@dartmouth.edu
    Send bugs, suggestions and mods to bug-gnuplot@dartmouth.edu

    If your see the Terminal type set to 'x11' then you are on an X windows device and you can see the the output for any plot command in a new window. For example the

    plot sin(x)

    command will produce a window with the the plot:

    Sin Curve plot

    To exit your gnuplot session type:


  • Making a plot to be displayed on a web page

    To make a copy of your plot for a web page, change the output format to "png," set the name of the output file and type the plot command again (or simply replot to save the current picture).

    set terminal png
    set output 'fig.png'
    plot sin(x)

    Then the sin(x) plot in the fig.png file can be display using the Firefox browser as shown below:

    Sin Plot in Netscape

  • Printing from Gnuplot

    To print your plot, change the output format to "postscript," set the name of the output file to the print command and type the plot command again (or simply replot to print the current picture).

    set terminal postscript
    set output '|lpr'
    plot sin(x)

    1. Make sure you begin the command with the pipe symbol: |. If you do not, Gnuplot will save your postscript output in a file.
    2. The lpr command will print to the printer you specified in your PRINTER environment variable or smips if you did not specify a printer.
  • on-line help

    The Gnuplot online help is all text-based. To see the online help, type the gnuplot command help. Make sure you watch the prompt. When you get back to the gnuplot> prompt, you can continue and type more gnuplot commands.