faq.txt

智能画图软件

                                  Gnuplot FAQ

   This document deals with gnuplot version 4.0 which is the latest official
   release as of April 2004.
   Its version is $Revision: 1.15 $, dated $Date: 2004/04/14 13:18:59 $.

Contents

     * 0 Meta - Questions
          * 0.1 Where do I get this document?
          * 0.2 Where do I send comments about this document?
     * 1 General Information
          * 1.1 What is gnuplot?
          * 1.2 How did it come about and why is it called gnuplot?
          * 1.3 What does gnuplot offer?
          * 1.4 Is gnuplot suitable for scripting?
          * 1.5 Can I run gnuplot on my computer?
          * 1.6 Legalities
          * 1.7 Does gnuplot have anything to do with the FSF and the GNU
            project?
          * 1.8 Where do I get further information?
     * 2 Setting it up
          * 2.1 What is the current version of gnuplot?
          * 2.2 Where can I get gnuplot?
          * 2.3 Where can I get current development version of gnuplot?
          * 2.4 How do I get gnuplot to compile on my system?
          * 2.5 What documentation is there, and how do I get it?
          * 2.6 Worked examples
          * 2.7 How do I modify gnuplot, and apply 'patches'?
     * 3 Working with it.
          * 3.1 How do I get help?
          * 3.2 How do I print out my graphs?
          * 3.3 How do I include my graphs in <word processor>?
          * 3.4 How do I edit or post-process a gnuplot graph?
          * 3.5 How do I change symbol size, line thickness and the like?
          * 3.6 How do I generate plots in GIF format?
          * 3.7 Can I animate my graphs?
          * 3.8 How do I plot implicit defined graphs?
          * 3.9 How to fill an area between two curves
          * 3.10 Pm3d splot from a datafile does not draw anything
          * 3.11 Drawing a (color) map, i.e. 2D projection of 3D data
          * 3.12 How to overlay dots/points scatter plot onto a pm3d
            map/surface
          * 3.13 How to draw black contour plot, and contours with labels
          * 3.14 How to overlay contour plot over pm3d map/surface
          * 3.15 Color facets with pm3d
          * 3.16 Palette for printing my color map on color as well as
            blank&white printer?
     * 4 Wanted features
          * 4.1 What's new in gnuplot 3.7, 4.0 etc?
          * 4.2 Does gnuplot support a driver for <graphics format>?
          * 4.3 Does gnuplot have hidden line removal?
          * 4.4 Does gnuplot support bar-charts/histograms/boxes?
          * 4.5 Does gnuplot support pie charts?
          * 4.6 Does gnuplot quarterly time charts?
          * 4.7 Can I put multiple pages on one page?
          * 4.8 Does gnuplot support multiple y-axes on a single plot?
          * 4.9 Can I put both commands and data into a single file?
          * 4.10 Can I put Greek letters and super/subscripts into my labels?
          * 4.11 How do I include accented characters
          * 4.12 Can I do 1:1 scaling of axes?
          * 4.13 Can I put different text sizes into my plots?
          * 4.14 How do I skip data points?
          * 4.15 How do I plot every nth point?
          * 4.16 How do I plot a vertical line?
          * 4.17 How do I plot data files
          * 4.18 How do I replot multiplot drawing
     * 5 Miscellaneous
          * 5.1 I've found a bug, what do I do?
          * 5.2 Can I use gnuplot routines for my own programs?
          * 5.3 What extensions have people made to gnuplot? Where can I get
            them?
          * 5.4 I need an integration, fft, iir-filter,...!
          * 5.5 Can I do heavy-duty data processing with gnuplot? or What is
            beyond gnuplot?
          * 5.6 Mouse in my interactive terminal does not work
          * 5.7 How to use hotkeys in my interactive terminals
          * 5.8 I have ported gnuplot to another system, or patched it. What
            do I do?
          * 5.9 I want to help in developing the next version of gnuplot.
            What can I do?
          * 5.10 Open questions for inclusion into the FAQ?
     * 6 Making life easier
          * 6.1 How do I plot two functions in non-overlapping regions?
          * 6.2 How do I run my data through a filter before plotting?
          * 6.3 How do I make it easier to use gnuplot with LATEX?
          * 6.4 How do I save and restore my settings?
          * 6.5 How do I plot lines (not grids) using splot?
          * 6.6 How do I plot a function f(x,y) that is bounded by other
            functions in the x-y plane?
          * 6.7 How do I turn off <feature> in a plot?
          * 6.8 How do I call gnuplot from my own programs?
          * 6.9 What if I need h-bar (Planck's constant)?
          * 6.10 How do a produce blank output page?
     * 7 Common problems
          * 7.1 Gnuplot is not plotting any points under X11! How come?
          * 7.2 My isoline data generated by a Fortran program is not handled
            correctly. What can I do?
          * 7.3 Why does gnuplot ignore my very small numbers?
          * 7.4 Gnuplot is not plotting on the screen when run from command
            line via 'gnuplot filename.gp'
          * 7.5 My formulas (like 1/3) are giving me nonsense results! What's
            going on?
          * 7.6 Set output 'filename' isn't outputting everything it should!
          * 7.7 When using the LATEX-terminal, there is an error during the
            LATEX-run!
          * 7.8 The exit command does not work as documented!
          * 7.9 I can't find the demos and example files at the URLs in the
            documentation!
          * 7.10 Calling gnuplot in a pipe or with a gnuplot-script doesn't
            produce a plot!
     * 8 Credits


0 Meta - Questions

0.1 Where do I get this document?

   The newest version of this document is on the web at
   http://www.gnuplot.info/faq/.

   This document was/is posted sometimes to the newsgroups
    ~comp.graphics.apps.gnuplot.

0.2 Where do I send comments about this document?

   Send comments, suggestions etc via email to the developer mailing list
   [e-mail]. Please contribute your suggestions
   with respect to the file faq.tex available from
   http://cvs.sourceforge.net/viewcvs.py/gnuplot/faq/.


1 General Information

1.1 What is gnuplot?

   gnuplot is a command-driven interactive function plotting program. It can
   be used to plot functions and data points in both two- and
   three-dimensional plots in many different formats. It is designed
   primarily for the visual display of scientific data. gnuplot is
   copyrighted, but freely distributable; you don't have to pay for it.

1.2 How did it come about and why is it called gnuplot?

   The authors of gnuplot are: Thomas Williams, Colin Kelley, Russell Lang,
   Dave Kotz, John Campbell, Gershon Elber, Alexander Woo and many others.

   The following quote comes from Thomas Williams:

     I was taking a differential equation class and Colin was taking
     Electromagnetics, we both thought it'd be helpful to visualize the
     mathematics behind them. We were both working as sys admin for an EE
     VLSI lab, so we had the graphics terminals and the time to do some
     coding. The posting was better received than we expected, and prompted
     us to add some, albeit lame, support for file data.

     Any reference to GNUplot is incorrect. The real name of the program is
     "gnuplot". You see people use "Gnuplot" quite a bit because many of us
     have an aversion to starting a sentence with a lower case letter, even
     in the case of proper nouns and titles. gnuplot is not related to the
     GNU project or the FSF in any but the most peripheral sense. Our
     software was designed completely independently and the name "gnuplot"
     was actually a compromise. I wanted to call it "llamaplot" and Colin
     wanted to call it "nplot." We agreed that "newplot" was acceptable but,
     we then discovered that there was an absolutely ghastly pascal program
     of that name that the Computer Science Dept. occasionally used. I
     decided that "gnuplot" would make a nice pun and after a fashion Colin
     agreed.

1.3 What does gnuplot offer?

     * Plotting two-dimensional functions and data points in many different
       styles (points, lines, error bars)
     * Plotting three-dimensional data points and surfaces in many different
       styles (contour plot, mesh)
     * Algebraic computation in integer, float and complex arithmetic
     * User-defined functions and hot-keys
     * Support for a large number of operating systems, graphics file formats
       and output devices
     * Extensive on-line help
     * TEX-like text formatting for labels, titles, axes, data points
     * Interactive command line editing and history (most platforms)

1.4 Is gnuplot suitable for scripting?

   Yes. Gnuplot can read in files containing additional commands during an
   interactive session, or it can be run in batch mode by piping a
   pre-existing file or a stream of commands to stdin. Gnuplot is used as a
   back-end graphics driver by such higher-level mathematical packages as
   Octave, and can easily be wrapped in a cgi script for use as a web-driven
   plot generator.

1.5 Can I run gnuplot on my computer?

   Gnuplot is available for a number of platforms. These are: Unix (X11 and
   NeXTSTEP), Linux, VMS, OS/2, MS-DOS, Amiga, MS-Windows, OS-9/68k, Atari
   ST, BeOS, and Macintosh.

   Please notify the FAQ-maintainer of any further ports you might be aware
   of.

   You should be able to compile the gnuplot source more or less out of the
   box on any reasonable standard (ANSI/ISO C, POSIX) environment.

1.6 Legalities

   Gnuplot is freeware authored by a collection of volunteers, who cannot
   make any legal statement about the compliance or non-compliance of gnuplot
   or its uses. There is also no warranty whatsoever. Use at your own risk.

   Citing from the README of a mathematical subroutine package by R. Freund:

     For all intent and purpose, any description of what the codes are doing
     should be construed as being a note of what we thought the codes did on
     our machine on a particular Tuesday of last year. If you're really
     lucky, they might do the same for you someday. Then again, do you really
     feel *that* lucky?

1.7 Does gnuplot have anything to do with the FSF and the GNU project?

   Gnuplot is neither written nor maintained by the FSF. It is not covered by
   the General Public License, either. It used to be distributed by the FSF,
   however, due to licensing issues it is no longer.

   Gnuplot is freeware in the sense that you don't have to pay for it.
   However it is not freeware in the sense that you would be allowed to
   distribute a modified version of your gnuplot freely. Please read and
   accept the Copyright file in your distribution.

1.8 Where do I get further information?

   See the main gnuplot web page http://www.gnuplot.info and references
   therein, mainly gnuplot links http://gnuplot.sourceforge.net/links.html.

   Some documentation and tutorials are available in other languages than
   English. See http://gnuplot.sourceforge.net/help.html, section "Localized
   learning pages about gnuplot", for the most up-to-date list.


2 Setting it up

2.1 What is the current version of gnuplot?

   The current released version of gnuplot is 4.0.

2.2 Where can I get gnuplot?

   The best place is definitely http://www.gnuplot.info. From there you find
   various pointers to other sites.

   The source distribution ("gnuplot-4.0.0.tar.gz" or a similar name) is
   available from the official distribution site and its mirrors.

   The main server is ftp.gnuplot.info in /pub/gnuplot/. This server is
   mirrored by several others, among those are
     * mirror.aarnet.edu.au in /pub/gnuplot/
     * ftp.dartmouth.edu in /pub/gnuplot/
     * ftp.irisa.fr in /pub/gnuplot/
     * ftp.gnuplot.vt.edu in /pub/gnuplot/

   As of June 1999, the gnuplot distribution is also mirrored at the
   Comprehensive TeX Archive Network (CTAN) in the graphics/gnuplot
   directory. See
     * http://www.ctan.org/.

   The following platform-specific sites below still exist, but may or may
   not still hold gnuplot executables.

     * Source and binary distributions for the Amiga are available on Aminet
       ftp.wustl.edu in  aminet/ and its mirrors, for example ftp.uni-kl.de,
       oes.orst.edu or ftp.luth.se.

     * MS-DOS and MS-Windows binaries are available from the above servers
       and are called for example gp37dos.zip, gp37dj.zip, gp37w16.zip,
       gp37mgw.zip, gnuplot3.7cyg.zip. OS/2 binaries are called gp37os2.zip.

     * The NeXTSTEP front end can be found at next-ftp.peak.org in
       /pub/next/binaries/plotting/Gnuplot1.2_bin.tar.Z.

     * A version for OS-9/68K can be found at cabrales.cs.wisc.edu in
       /pub/OSK/GRAPHICS/gnuplot32x.tar.Z; it includes both an X-Window
       Systems and a non - X-Window Systems version.

     * Versions for the Atari ST and TT, which include some GEM windowing
       support, are available from ftp.uni-kl.de in /pub/atari/graphics/, as
       gplt35st.zip and gplt35tt.zip. They work best under MiNT.

     * Executable files, plus documentation in Japanese, exist for the X680x0
       on ftp.csis.oita-u.ac.jp in /pub/x68k/fj.binaries.x68000/vol2.

2.3 Where can I get current development version of gnuplot?

   The development version of gnuplot is availble as a cvs source tree online
   for direct browsing from http://www.sourceforge.net/projects/gnuplot/,
   section "CVS". You can download all current sources according to the
   documentation therein; for example by a sequence of commands like

   export CVSROOT=:pserver:[e-mail]:/cvsroot/gnuplot
   cvs login
   cvs -z3 checkout gnuplot

   Further, before the ./configure command of gnuplot compilation phase, you
   have to execute ./prepare to create the up-to-date configure files.

   There are no official preliminary binary releases of gnuplot: you have to
   compile it yourself. However, you may find unofficial binary releases for
   some platforms, like OS/2, Windows or Macintosh.

   Important note: questions related to the development version should go to
   [e-mail].

2.4 How do I get gnuplot to compile on my system?

   As you would any other installation. Read the files README.1ST and README.

     * For Unix, use ./configure (or ./configure -prefix=$HOME/usr for an
       installation for a single user), make and finally make install or make
       install-strip, the latter for smaller executables without debugging
       information. If you want to make a RPM package, then replace the
       latest step by checkinstall or checkinstall make install-strip,
       supposing the package checkinstall on your machine.
     * For DOS, if you are using bash and DJGPP, you can just run
       djconfig.sh.
     * For other platforms, copy the relevant makefile (e.g. makefile.os2 for
       OS/2, or makefile.mgw or makefile.cyg for Windows) from config/ to
       src/, optionally update options in the makefile's header, then change
       directory to src and run make.

2.5 What documentation is there, and how do I get it?

   The documentation is included in the source distribution. Look at the docs
   subdirectory, where you'll find

     * a Unix man page, which says how to start gnuplot
     * a help file, which also can be printed as a manual
     * a tutorial on using gnuplot with LATEX
     * a quick reference summary sheet for TEX only

   The documentation is built during installation if you have LATEX installed
   on your system, look in the directories docs and tutorial. make pdf in the
   docs subdirectory will make a gnuplot.pdf hypertext file ready for