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ƨt$PvW9&t~t9&>zu$PvW$PvW$PvWw$PvWh9&>ju9&X&&$ډFVRP9&69&6$PP%Pvv vvvW%PvW9&6&69&6&6:&6&6#%Pvv vvvWB:&6&6:&6&6:&6&60%Pvv vvvW=%PvWD:&&&(0T|RPE%Pvv vvvW vW" 9&$PP] FpP FVv~vvO%PvV vV" PvVj! FPQ\%QJ] PvV" PvVJ] PvvvJ] F~~;~v^^؋NJ*3QNJ*&3ZF;v|։~v] v_%PvV PvV" PvVJ] FF=vP FVvv`  t 2PP]  :&uvv`  t|] u t 3P( -*ui%PvV vV2 ui6`#6^#vVF  uN6p#6n#vvF  t~9&X&&e%PFPW ƋFv2PP] 9&X&&V\2PP]  :&u9&X&&ˎ9&X&&k%PFPV NjFvW 3^_]U WVFdžPƆ{dž8o%:dždž@~%BdžD%FdžH%J+NL9& & vx~prt89 +&G&n9&9ptH9&9vt=PP9&6&6`%P9&6&6ZT %P| T :&P FVpP FV+FF{{<vv~uZ6`#6^#%P~V P~V" P~VJ] easily. Q4.8: Can I put tic marks for x and y axes into 3d plots? In version 3.5, you can. Q4.9: Does gnuplot support a driver for ? To see a list of the available graphic drivers for your installation of gnuplot, type "set term". Some graphics drivers are included in the normal distribution, but are uncommented by default. If you want to use them, you'll have to change ~gnuplot/term.h. Q4.10: Can I put different text sizes into my plots? If you use PostScript output, you can use Dave Denholm's and Matt Heffron's updated PostScript driver, /sotona.phys.soton.ac.uk:/mattpost.trm (see also Q4.6). Section 5: Miscellaneous Q5.1: I've found a bug, what do I do? First, try to see whether it actually is a bug, or whether it is a feature which may be turned off by some obscure set - command. Next, see wether you have an old version of gnuplot; if you do, chances are the bug has been fixed in a newer release. If, after checking these things, you still are convinced that there is a bug, proceed as follows. If you have a fairly general sort of bug report, posting to comp.graphics.gnuplot is probably the way to go. If you have investigated a problem in detail, especially if you have a context diff that fixes the problem, please e-email a report to bug-gnuplot@dartmouth.edu. The bug-gnuplot list is for reporting and collecting bug fixes, the comp.graphics.gnuplot mailing list will be more help for finding work arounds or actually solving gnuplot related problems. If you do send in a bug report, be sure and include the version of gnuplot (including patchlevel), terminal driver, operating system, an exact description of the bug and input which can reproduce the bug. Also, any context diffs should be referenced against the latest official version of gnuplot if at all possible. Q5.2: Can I use gnuplot routines for my own programs? Yes. John Campbell has written gplotlib, a version of gnuplot as C subroutines callable from a C program. This is available as gplotlib.tar.Z on the machine ftp.nau.edu in the directory /pub/gplotlib.tar.Z. It is also included in the gpcontrb distribution in the campbell subdirectory. Q5.3: What extensions have people made to gnuplot? Where can I get them? [This is still hazy; please check this out and see whether it is correct. Ed.] Extensions have been put into the file gpcontrb.tar.Z, which is available with the 3.5 release, from the same places you can download the main distribution from. Note that it has a size of 3.5 megabytes. It contains the following subdirectories: bigler subdirectory: From: bigler@cicg-calcul.grenet.fr Subject: Multiple plots from a Fortran program budelsky subdirectory: From: budelsky@haegar.ikp.uni-koeln.de Subject: This is the information file for porting gnuplot 3.2 to OS-9/68000 byrne subdirectory: From: "Margaret R. Byrne" Subject: congp3d3 preprocessor to draw contour plots on irregular regions. clark subdirectory: From: Michael Clark Subject: data filtering: adds point_skip & point_offs clift subdirectory: From: ssclift@neumann.uwaterloo.ca (Simon Clift) Subject: Re: Running gnuplot from Fortran, (and C) green subdirectory: From: Roque Donizete de Oliveira Subject: PostScript Greek symbols in gnuplot, new prologue hanna subdirectory: From: gregor@kafka.saic.com (gregg hanna) Subject: x11-library mode, gnulib_x11.[c,h], xlibtest.c,makefile.xlib klosowski subdirectory: From: Carsten Steger Subject: New file "klein.dat" From: przemek@rrdstrad.nist.gov (Przemek Klosowski) Subject: calling gnuplot from Fortran kocaturk subdirectory: From: mustafa@seas.smu.edu (Mustafa Kocaturk) Subject: Histograms in gnuplot richardson subdirectory: From: amr@chiton.ucsd.edu (Tony Richardson) Subject: Programmatic control of gnuplot from Unix rosendorf subdirectory: From: prf@jprix.che.wisc.edu Subject: Multiple plots on a page vanzandt subdirectory: From: James R. Van Zandt Subject: Spline generating program white subdirectory: From: gwhite@bionet.bio.dfo.ca Subject: gnuplot 3.2 for Titan 3000 woo subdirectory: From: "Alex Woo" Subject: two additional title lines and fixes to errorbar style yamamoto subdirectory: From: "NOBORU YAMAMOTO " Subject: Re: gnuplot on Apple Macintosh, "diff -c" of version 3.0 (now includes binaries) castro subdirectory: From: maurice@bruce.cs.monash.edu.au (Maurice Castro) Subject: Controlling gnuplot from another Windows program grammes subdirectory: From: ph12hucg@rz.uni-sb.de (Carsten Grammes) Subject: Nonlinear least squares fit mechanism henke subdirectory: From: mgr@asgard.bo.open.de (Lars Hanke) Subject: Re: Changes to gnuplot 3.3b9 walton subdirectory: From: dwalton@athena.mit.edu (Dave Walton) Subject: Inter Process Communication stuff Q5.4: Can I do heavy - duty data processing with gnuplot? Gnuplot alone is not suited very well for this. One thing you might try is fudgit, an interactive multi-purpose fitting program written by Martin-D. Lacasse (isaac@frodo.physics.mcgill.ca). It can use gnuplot as its graphics back end and is available from ftp.physics.mcgill.ca in /pub/Fudgit/fudgit_2.33.tar.Z [132.206.9.13], and from the main Linux server, tsx-11.mit.edu [18.172.1.2] and its numerous mirrors around the world as /pub/linux/sources/usr.bin/fudgit-2.33.tar.z. Versions are available for AIX, Data General, HP-UX, IRIX 4, Linux, NeXT, Sun3, Sun4, Ultrix, OS/2 and MS-DOS. The MS-DOS version is available on simtel20 mirrors (simtel20 itself has closed down) in the "math" subdirectory as fudg_231.zip. Carsten Grammes has written a fitting program which goes together with gnuplot; it is called gnufit and is available from the official gnuplot sites, as the files gnufit12.info, gnufit12.tar.gz (source) and gft12dos.zip (MS-DOS). Michael Courtney has written a program called lsqrft, which uses the Levenberg - Marquardt - Algorithm for fitting data to a function. It is avialiable from ftp.cdrom.com as /pub/os2/2_x/unix/lsqrft13.zip; sources, which should compile on Unix, and executables for MS-DOS and OS/2 2.x are included. There is an interface to the OS/2 presentation manager. You might also want to look at the applications developed by the Software Tools Group (STG) at the National Center for Supercomputing Applications. Ftp to ftp.ncsa.uiuc.edu [141.142.20.50] and get the file README.BROCHURE for more information. Q5.5: I have ported gnuplot to another system, or patched it. What do I do? If your patch is small, mail it to bug-gnuplot@dartmouth.edu, with a thorough description of what the patch is supposed to do, which version of gnuplot it is relative to, etc. Please don't mail it to the FAQ maintainer. If your modifications are extensive (such as a port to another system), upload your modifications to ftp.dartmouth.edu:/pub/dropoff. Please drop a note to David.Kotz@dartmouth.edu, the maintainer of the gnuplot subdirectory there, plus a note to bug-gnuplot@dartmouth.edu. Section 6: Making life easier Q6.1: How do I plot two functions in non - overlapping regions? Use a parametric plot. An example: set parametric a=1 b=3 c=2 d=4 x1(t) = a+(b-a)*t x2(t) = c+(d-c)*t f1(x) = sin(x) f2(x) = x**2/8 plot [t=0:1] x1(t),f1(x1(t)) title "f1", x2(t), f2(x2(t)) title "f2" Q6.2: How do I run my data through a filter before plotting? If your system supports the popen() - function, as Unix does, you should be able to run the output through another process such as a short awk program (use the "help plot datafile" command for an example). Unfortunately, in 3.2, there is a rather short limitation on the maximum argument length, so your command line may be truncated (usually, this will mean that awk cannot find the filename). Also, you may need to escape the $ - characters in your awk programs. As of version 3.4, gnuplot includes the thru - keyword for the plot command for running data files through a gnuplot - defined function. You can also get divhack.trm from sotona.phys.soton.ac.uk[152.78.192.42] via anonymous ftp. It allows expressions of the kind gnuplot> plot "datafile" using A:B:C where A,B,C,... are now either a column number, as usual, or an arbitrary >expression enclosed in ()'s, and using $1,$2,etc to access the data columns. Q6.3: How do I make it easier to use gnuplot with LaTeX? There is a set of LaTeX macros and shell scripts that are meant to make your life easier when using gnuplot with LaTeX. This package can be found on ftp.dartmouth.edu [129.170.16.54] in pub/gnuplot/latex.shar, by David Kotz. For example, the program "plotskel" can turn a gnuplot-output file plot.tex into a skeleton file skel.tex, that has the same size as the original plot but contains no graph. With the right macros, the skeleton can be used for preliminary LaTeX passes, reserving the full graph for later passes, saving tremendous amounts of time. Q6.4: How do I save and restore my settings? Use the "save" and "load" commands for this; see "help save" and "help load" for details. Q6.5: How do I plot lines (not grids) using splot? If the data in a data file for splot is arranged in such a way that each one has the same number of data points (using blank lines as delimiters, as usual), splot will plot the data with a grid. If you want to plot just lines, use a different number of data entries (you can do this by doubling the last data point, for example). Don't forget to set parametric mode, of course. Q6.6: How do I plot a function f(x,y) which is bounded by other functions in the x-y plain? An example: f(x,y) = x**2 + y **2 x(u) = 3*u yu(x) = x**2 yl(x) = -x**2 set parametric set cont splot [0:1] [0:1] u,yl(x(u))+(yu(x(u)) - yl(x(u)))*v,\ f(x(u), (yu(x(u)) - yl(x(u)))*v) Q6.7: How do I get rid of ? Usually, there is a set command to do this; do a gnuplot> ?set no for a short overview. Section 7: Known problems Q7.1: Gnuplot is not plotting any points under X11! How come? Very probably, you still are using an old version of gnuplot_x11. Remove that, then do a full installation. On VMS, you need to make several symbols: $ gnuplot_x11 :== $disk:[directory]gnuplot_x11 $ gnuplot :== $disk:[directory]gnuplot.exe $ def/job GNUPLOT$HELP disk:[directory]gnuplot.hlb Then run gnuplot from your command line, and use gnuplot> set term x11 Q7.2: My isoline data generated by a Fortran program is not handled correctly. pt. For emTeX (popular for MS-DOS), you can use emTeX, otherwise use the LaTeX terminal type, which generates a picture environment. If nothing else helps, try using the pgm or ppm format and converting it to a bitmap format your favourite word processor can understand. An invaluable tool for this is Jef Poskanzer's PBMPLUS package. The PBMPLUS package is available in the contrib distribution for Xwindows. The original site for this is ftp.x.org:/contrib, there are many mirrors, e.g. ftp.th-darmstadt.de:/pub/X11/contrib or sunsite.unc.edu:/pub/X11/contrib. The most recent release of pbm by the author is dated December 91 and is called pbmplus10dec91.tar.Z There is new version including lots of patches from the net that is not maintained by the author called netpbm, with the newest version called netpbm-7dec1993.tar.gz. Check archie (see Q2.2) for an archive site near you. Section 4: Wanted features in gnuplot Q4.1: Does gnuplot have hidden line removal? Version 3.5 supports hidden line removal on all platforms except MS-DOS; use the command set hidden3d If someone can solve the 64K DGROUP memory problem, gnuplot would support hidden line removal on MS-DOS as well. Version 3.2 supports limited hidden line removal. Q4.2: Does gnuplot support bar-charts/histograms/boxes? As of version 3.4, it does. Q4.3: Does gnuplot support multiple y-axes on a single plot? No. Q4.4: Can I put multiple plots on a single page? Look at the rosendorf subdirectory in the gpcontrb distribution; if you are using PostScript output, check out mpage, which can be ftp'd from ftp.eng.umd.edu:pub/misc/mpage-2.tar.Z Q4.5: Can I put both data files and commands into a single file? Alex Woo has just put out an unofficial modification for beta test, which does exactly this. Otherwise, you might consider using Fudgit, which can do it. Q4.6: Can I put Greek letters and super/subscripts into my labels? You might try using the LaTeX terminal type and putting textavid Kotz, Rob Cunningham, Daniel Lewart and Alex Woo. Reworked by Thomas Koenig from a draft by Alex Woo, with corrections and additions from Alex Woo, John Campbell, Russell Lang, David Kotz and many corrections from Daniel Lewart. -- Thomas Koenig, ig25@rz.uni-karlsruhe.de, ig25@dkauni2.bitnet The joy of engineering is to find a straight line on a double logarithmic diagram.