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Dataplot Frequently Asked Questions (FAQS)
Installation Questions
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Printing Questions
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Data and I/O Questions
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Graph Construction Questions
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Fitting and Data Analysis Questions
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Dataplot Programming Questions
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Installation Questions
How Do I Download and Install Dataplot?
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Question: How do download and install the Dataplot
software?
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Instructions for downloading and installing Dataplot can be found at the download web page.
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The GUI Version of Dataplot Does Not Run Under Windows, What
Do I Do?
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Question: The GUI version of Dataplot does not run
under Windows, what do I do?
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If the GUI version of Dataplot fails to run on the PC, check the following:
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The Command Line Version of Dataplot Gives Me a Blank Screen,
What Do I Do?
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Question: The command line version of Dataplot on
the PC gives me a blank screen, what do I do?
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The PC can run in two different color modes. The first, called true or direct color, specifies a red, blue, and green component (i.e., RGB), each with an integer value between 0 and 255. Alternatively, a specific number of colors can be supported (e.g., 255). The non-RGB mode is more common on older computers with display cards with more limited memory. In this mode, there is typically a trade-off between the number of colors and the video resolution (i.e., as the resolution goes up, the number of available colors goes down). The Dataplot command line version on the PC is created with the Compaq Visual compiler (previously the Microsoft Fortran compiler) using the QuickWin graphics library. This library does not provide an automatic method for determining which color mode is in effect. The blank screen is caused by Dataplot assuming the wrong color mode. By default, Dataplot uses the non-RGB color mode. If you get a blank screen (this is actually a black foreground on a black foreground), then add the option "-true" option when you invoke DATAPLOT.EXE. For example,
The color mode can be changed by the user under the Control Panel. If the color mode is changed on your machine, you may need to modify the "-true" switch (i.e., either add it or remove it).
The Fonts in the GUI Menus Are Too Small, What Do I Do?
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Question: The fonts in the GUI menus are too small, what
do I do?
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There is a configuration file for the Tcl/Tk scripts. You can change the size of the requested fonts in this configuration file. Note that you can also change the default editor and the default web browser in this file as well. This configuration file is an ASCII file that can be edited with your favorite text editor. The comments in the configuration file give the specific instructions for modifying the font sizes. For Unix platforms, the configuration file is located in the "frscript" subdirectory in the Dataplot auxillary directory (/usr/local/lib/dataplot by default). The name of the file is "xdpConfig". If you copy this file to your home directory, the version in the home directory overrides the version in "frscript". You can modify the "frscript" version to set site wide defaults and you can, optionally, have the version in your home directory to set personal defaults. Font sizes will typically be a site wide default. On the other hand, the choice of default browser and editor is often a personal default. For Windows platforms, the default location for the configuration file is "C:\DATAPLOT\FRSCRIPT\XDPCONFIG". Note that the "DP.BAT" script (which is the file that initiates the GUI) is setup to copy either XDPCWNNT (for NT 4 and Windows 2000) or XDPCWN95 (for Windows 95, 98, ME) to XDPCONFIG. This is due to the fact that the different versions of Windows use slightly different paths for the browsers, Notepad, and Wordpad. That is, you should edit either XDPCWN95 or XDPCWNNT rather than XDPCONFIG since XDPCONFIG gets overwritten whenever you run DP.BAT.
Can I Redistribute Dataplot with my Own Applications?
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Question: Can I redistribute Dataplot with my own
applications?
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You are free to redistribute Dataplot as part of your own applications software. If you want to include the Dataplot CD or any printed documentation, we request that you provide these rather than sending your customers to us (i.e., we will give you a copy, then you are free to make as many copies as you need for your own purposes).
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How Do I Use My PC as a Terminal for Running Dataplot on
Another Platform (e.g., Unix)?
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Question: I am using my IBM PC compatible to run
Dataplot on a remote workstation. I do not particulary want
to install and run Dataplot locally on my PC, but I
would still like to generate high quality graphics
on my screen.
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When used as a terminal to a remote computer, the graphics capability is determined by the communications software. The type of graphics protocol supported varies widely depending on the specific communications software you have. The most common case is that Dataplot is running on a remote Unix workstation. In this case, the recommended solution is to obtain and install an X11 software package on your PC. This allows your PC to operate as an X11 terminal. If you have an ethernet connection, this is probably the most satisfactory approach. A number of commercial implemenatations of X11 software are available for the PC. X11 is a protocol designed to provide device independent graphics and windowing in a network environment. It is the standard protocol for most Unix workstations. As a technical note, the X11 library comes in three layers:
For non-X11 mainframes (e.g., Vax/VMS) or for access over a telephone line, the communications software you use may provide for some type of graphics emulation. Some communications software may not support any graphics emulation capability. Dataplot supports the following graphics protocols that may be useful for this purpose:
If your communications protocol does not support graphics emulation, you may want to investigate the possibility of obtaining a communications program that does support one of the above graphics protocols. You may want to check with your local system adminstrators to see if they can provide guidance for your site.
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Printing Questions
How Do I Import a Dataplot Graph Into Word or Power Point
(or Some Other External Program)?
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Question: How do I import a Dataplot graphic into
Word or Power Point or some other external program?
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It is common to want to import a Dataplot graphic into a report written in Word, WordPerferct, Latex, or some other word processor or page publishing system. You may also want to include Dataplot graphics into a Power Point presentation or import the graph into a graphics editing program such as Adobe Illustrator. The issues involved in this are given on the Graphics Devices web page.
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How Do I Print My Dataplot Graphics in the Unix Version of
Dataplot?
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Question: How do I print my Dataplot graphics in
the Unix version of Dataplot?
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Printing the graphics files dppl1f.dat or dppl2f.dat is performed in the standard way for your operating system. For example, on Unix you would enter the Unix command
Under Unix, Dataplot can generate either Postscript (DEVICE 2 POSTSCRIPT) or HPGL (DEVICE 2 HPGL LASER). If you have a non-supported printer (e.g., a DeskJet or InkJet type printer), then investigate Ghostview/Ghostscript. First, check the Ghostview/Ghostscript documentation to see if your printer is supported. If so, then check to see if Ghostview/Ghostscript is already installed on your system. If not, you need to download and install it (hopefully, your local system administrator will be willing to help). Note that in Unix, there is not a common "graphics device" interface for printers. The protocol for a given printers has to be explicitly supported. For this reason, Postscript is the preferred protocol for printers in the Unix world and the list of supported printers in Ghostview may be smaller in the Unix implementation than the Windows implementation. This is more likely to be an issue for PC based Unix/Linux platforms than for workstation based platforms.
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How Do I Print Dataplot Graphics in the Windows Version of
Dataplot?
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Question: How do I print Dataplot graphics in the
Windows version of Dataplot?
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This issue is discussed in detail on the Graphics Devices web page.
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How Do I Print the Current Screen Plot (PP) Under Unix and
Windows?
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Question: How do I print the current screen plot
(PP) under Unix and Windows?
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In UNIX, the PP command to print the last plot on the screen works, but sends the plot off to the wrong printer; how do I get PP to send the plot to the correct printer? In UNIX, Dataplot's PP command sends the plot off to your current default printer. To determine the current printer, enter from UNIX:
For Windows, there are two basic cases that we will consider separately:
For the first case, Dataplot supports both Postscript and HP-GL emulation directly. By default, the Dataplot PP command issues the following command:
DEVICE 3 HPGL LASERJET
Case 2: Generic Windows Printer Alternatively, you can use a generic Windows printer. Dataplot does not support this directly. Instead, it uses the freely downloadable Ghostview/Ghostscript software (Ghostscript is a Postscript translator and Ghostview is a Windows program that uses Ghostscript to display or print Postscript files). Ghostview provides the command GSPRINT that will print a Postscript file on a generic Windows printer. In order to use a generic Windows printer, you need to do the following:
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How Do I Get a Named Print File
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Question: How do I get a named print file?
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Dataplot maintains three graphics devices. These can all be used simultaneously and independently. The graphics devices are:
DEVICE 2 output is generated to the file dppl1f.dat in your current directory DEVICE 3 output is generated to the file dppl2f.dat in your current directory There are 2 basic approaches to creating your own named plot files.
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How Do I Generate Portrait Mode Postscript Plots?
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Question: How do I generate a portrait-mode postscript
plot? In particular, How do I generate a plot of Y = x**2 with
titles and labels and have it in portrait mode as opposed to
the default landscape mode?
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The following code will generate the portrait-mode Postscript plot:
ORIENTATION PORTRAIT PLOT X**2 FOR X = 1 1 10 EXIT
ORIENTATION PORTRAIT FRAME COORDINATES 10 20 90 90 PLOT X**2 FOR X = 1 1 10 EXIT If you are generating multiple plots per page and you wish to have portrait mode output, then to additionally adjust the aspect ratio, you may also use the MULTIPLOT COORDINATES command which will adjust the size and position of the entire set of multiplots from its default of 15 20 85 90. An example of the use of that command is
In summary, therefore, for a 2 by 2 multiplot, the following code yields nice output for portrait mode:
. ORIENTATION PORTRAIT . MULTIPLOT 2 2 MULTIPLOT COORDINATES 10 20 90 90 FRAME COORDINATES 10 20 90 85 . CHARACTERS CIRCLE CHARACTER FILL ON CHARACTER HW 1 1.4 . Y1LABEL Y XLABEL X . PLOT X FOR X = 1 1 10 PLOT X**2 FOR X = 1 1 10 PLOT X**3 FOR X = 1 1 10 Y1LABEL OFFSET 10 PLOT X**4 FOR X = 1 1 10 . EXIT
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Data and I/O Questions
Can I Read Excel Files into Dataplot?
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Question: Can I read Excel (or other spreadsheet or
database programs) files into Dataplot?
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The short answer is no. Currently, if you have your data in an Excel spreadsheet, you must first save it as an ASCII file. Use the "File/Save As" menu. There are several ASCII options. For more information on reading the various types of ASCII files that Excel can generate, enter
This help entry summarizes the information on reading various types of ASCII files and specifically discusses reading ASCII files generated by Excel. We are also investigating support for ODBC databases on the Windows platforms. This would include the ability to read Excel files directly. Both of the Fortran compilers we now use for the Windows platform support the same third party software to provide this capability. We hope to incorporate this into a future (hopefully, near future) version of Dataplot.
What Types of Data Files Does Dataplot Read?
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Question: What types of data files does Dataplot read?
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Currently, Dataplot reads ASCII files. These files can be created either using your favorite text editor or as the output from an commercial software program or as output from one of your own programs. The standard format of the ASCII file is a rectangular block of data. That is, the columns represent variables and the rows represent observations (Dataplot assumes that all variables in a given file have the same number of observations). If your data files is structured so that rows represent variables and columns represent observations, then you can use the SERIAL READ command to read the data. Dataplot supports a number of commands for skipping header lines, restricting which rows and columns are read, and specifying a fixed format for the data. These are documented in Chapter 9 of Volume I of the Reference Manual. Dataplot does support unformatted Fortran files. This is typically reserved for very large data files to speed up the reading and writing of data files. Dataplto does not currently support reading generic binary files (e.g., binary data written from a C program). For details on using Fortran unformatted files, enter the Dataplot command HELP READ FORMAT (SET). For a discussion of various issues regarding reading ASCII files, enter the command
Can I Read Character Data into Dataplot?
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Question: Can I read character data into Dataplot?
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For the most part, no. Dataplot expects data entered using the READ command to be numeric data only. If your data file contains alphabetic data, then you must use either the COLUMN LIMITS or the READ FORMAT command to skip over the alphabetic data. There are two ways to support alphabetic data in Dataplot.
NOTE: Some additional commands allowing limited support for character data were implemented in the 2004 version of Dataplot. Check the NEWS entry for details.
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Graph Construction Questions
How Do I Position the Title?
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Question: How do I go about moving the title on my plot
down closer to the upper frame line?
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In Dataplot
the top of your screen is at 100 the top frame line of your plot is at 90 the title line is at 97 (= 7 units above the top frame line)
To make this permanent, put the appropriate TITLE OFFSET command in your DPLOGF.TEX so that it will be automatically executed upon entry into Dataplot.
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How Do I Reposition the Vertical Axis Label?
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Question: The default positioning of the left vertical
axis label (as obtained by the Y1LABEL command) is such that
the label happens to be overwriting the tic mark numbers. How
do I move the label to the left so as to avoid this overwriting?
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In Dataplot
the right edge of your screen is at 100 the left vertical frame line is at 15 the left vertical axis label is at 7 (8 units to the left of the axis line)
To make this permanent, put the appropriate Y1LABEL OFFSET command in your DPLOGF.TEX so that it will be automatically executed upon entry into Dataplot.
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How Do I Set the Margin Spacing Within a Plot?
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Question: Some of my plots have data points which end
up on the frame lines and so are hard to see and easy to
miss. How do I build in a buffer zone within a plot so that
the plot points are visibly off the frame lines?
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This problem is caused (by default) because the tic mark minimum and maximum are at the frame corners. The easiest way to solve the problem is to offset the minimum and maximum away from the corners. This is done via the TIC OFFSET command. The TIC OFFSET may be done either in data units or in screen (0 to 100) units. The most common offsetting is done in screen units. Thus, for example, to build in a 5% buffer zone inside all 4 frame lines of a plot, enter
TIC OFFSET 5 5
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How Do I Generate Text with Upper and Lower Case Script?
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Question: In a Dataplot macro, I had
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The case of output strings is controlled by various forms of the CASE command. The default is UPPER which means the default output case for titles, labels, tic labels, legends, text, etc. (regardless of the case of the input string as specified by the TITLE, LABEL, TIC LABEL, LEGEND, and TEXT commands) is UPPER (= upper case). Three cases are allowed:
LOWER (lower case) ASIS ("as is", whatever mixture you have in the string)
LABEL CASE ASIS TIC LABEL CASE ASIS LEGEND CASE ASIS CASE ASIS
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How Do I Encircle/Highlight Data Points On a Plot?
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Question: I have a plot of Y versus X. I would like
to draw the viewer's attention to a particular data point
on the plot by drawing a circle around that point (only). How
do I do that? In particular, suppose I have a plot of
Y = X**2 for X = 1 (at increments of 1) up to 10. Suppose I
want to draw a circle around the data point at X = 8 (that would
be Y = 64). How do I do that?
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The easiest way to do that is to make use of the Dataplot multitrace capability (via consecutive PLOT statements connected by AND) and
TITLE CASE ASIS TITLE DISPLACEMENT 2 LET X = SEQUENCE 1 1 10 LET Y = X**2 CHARACTERS X CIRCLE CHARACTER HW 2 1 5 4 LINES BLANK BLANK PLOT Y X AND PLOT Y X SUBSET X 7.5 TO 8.5
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How Do I Have Two Different Left/ |
Right Axis Labels?
Question: I have a function
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Inasmuch as the default Dataplot settings for tic labels are such that
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How Do I Correct an Oversized Default Font on the Screen?
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Question: In generating Dataplot graphics, I commonly use
the default font for graphics appearing on the screen
(= device 1), and postscript renditions of the same font for
paper output (= device 2). I notice that when I do
multiplotting (multiple plots on the same page) even though I
get nice postscript paper output plots with publication-quality
helvetica font, the multiple plots on the screen are of
considerably poorer quality. It seems that although the font on
paper output is scaled continuously and can get arbitrarily small
(while still maintaining high resolution), the font on the screen
appears limited as to how small it can get and thus
moderate-sized characters appear when much smaller characters
are needed--thus resulting in overwriting. How can I correct
this?
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The questioner's observation is correct: screen graphics for the default font is limited in size, whereas device 2 postscript paper output font is continuous. For 1-plot-per-page graphics, there is no problem; however, for multiplotting, there is a problem in how text appears on plots on the screen. The explanation for this requires an understanding of the distinction between hardware and software characters. When Dataplot draws text, it does so in one of the following two ways:
The problem with the oversized screen fonts is typically caused because the screen device is unable to scale hardware characters to the desired size. There are two solutions for this: Solution 1: The first solution is to globally (across all devices) change the font from the default (= tektronix = hardware generated text) font to one of the seven continuously-scaled fonts available in Dataplot:
This solution will yield good screen graphics and adequate postscript paper output. Solution 2: Prior to July 1996, solution 1 was the only solution. As of July, 1996, Alan Heckert of NIST has provided a more acceptable second solution. Solution 2 is to change the font from default to scalable for device 1 only (the screen), while maintaining a high-quality postscript rendition of the default font for device 2 (paper output). In practice, to maintain acceptably fast screen graphics, use the fastest scalable font (simplex). This solution will yield both good (simplex font) screen graphics, and excellent postscript (default font) paper output graphics. Some trial and error may be required due to the fact that the Postscript hardware fonts come out somewhat smaller than the Dataplot Hershey fonts.
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Fitting and Data Analysis Questions
How Do I Capture Regression Output to an External File?
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Question: How do I capture the text output from a
regression out to a file so that I can use it as part of a
report?
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The text output from the FIT command (or the text output from any Dataplot command for that matter) may be captured by use of the CAPTURE command. Thus if one wants to capture the text output from a quadratic fit out to the file XYZ., for example, then one would enter
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How Do I Access Regression Coefficient Standard Deviations?
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Question: When I do a regression, the coefficients become
Dataplot parameters (scalars) but the standard deviation of the
coefficients, though seen on the screen, are not saved as
Dataplot parameters. I would like to have the coefficient
standard deviations as parameters for printing and/or for
annotation on plots. How do I get these coefficient standard
deviations?
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Whenever a FIT command is executed, the coefficients and their standard deviations are copied out to file dpst1f.dat in your current directory. Thus to get the standard deviations, simply read them in (via the READ command), as in:
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Dataplot Programming Questions
How Do I Repeat Blocks of Commands?
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Question: How do I go about re-executing a previous
command or a previous set of commands?
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If you want to repeat a single command, then you may use the REPEAT (or R for short) command. To re-execute the last command, enter any of the following:
R REPEAT 1 R 1
L
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Where Should I Have the Dataplot Login File dplogf.tex?
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Question: I realize that Dataplot has a file named
DPLOGF.TEX (dplogf.tex on Unix) that will automatically be
executed upon entry into Dataplot. I also know that I can
usefully employ DPLOGF.TEX by storing commands in this ASCII
file that will override system defaults and put in place analyst
preferences. How can I create this file and what directory
should it go in?
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The ASCII file DPLOGF.TEX may be created by any convenient editor. Dataplot first looks for this file in the current directory. If found, the search is over and the commands are executed. If not found, the search continues. PC WINDOWS: Dataplot will look secondarily for DPLOGF.TEX in the Dataplot directory. By default, this directory is "C:\DATAPLOT". If you installed Dataplot in a different directory, you need to symbolically define the Dataplot directory by defining the variable DATAPLO$: in your AUTOEXEC.BAT file. If you installed Dataplot in the "D:\DATAPLOT" directory, then enter the command
Dataplot is typically executed with a shortcut to a batch file. For the command line version, the batch file is "DPCOMM.BAT" and for the GUI version the batch file is "DP.BAT". Both of these files contain a "SET DATAPLO$". If you did not use the default installation directory, then this line needs to be edited to reflect the correct location. For the command line version, if no SET DATAPLO$ variable is defined, Dataplot will search the "C:\DATAPLOT" directory for DPLOGF.TEX. UNIX: Pre-July 1996, no central directory existed for the dplogf.tex file and so the analyst had no choice but to have the same dplogf.tex in every directory where Dataplot might be run (a waste). Post-July 1996, Dataplot looks secondarily for dplogf.tex in the directory specified symbolically as $HOME in your .cshrc file. Thus in my .cshrc, I have a line:
If no DPLOGF.TEX is found, you will typically see an error message printed on the terminal indicating that Dataplot was unable to open the DPLOGF.TEX file. However, you can still continue with your Dataplot session. The only issue is that you need to be aware that no login file was run.
How Do I Integrate Dataplot With My Own Fortran or C Programs?
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Question: How do I integrate Dataplot with my own
Fortran/C programs?
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We consider integration in two basic senses.
First, we discuss invoking Dataplot from within a Fortran program (the basic idea is similar for a C program). The basic steps are as follows:
Can I Extract the Dataplot Source Code to Use in My Own Fortran
or C Programs?
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Question: Can I extract the Dataplot source code to use
in my own Fortran/C programs?
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The short answer is yes. The Dataplot source code is publically available and we do not place any restrictions on its use. However, the Dataplot code is not structured as independent libraries. This means that you will have to do a little work in order to use it with your own applications. In some cases, it is a fairly trivial process. In other cases, it may not be worthwhile. We note a few points that you need to be aware of.
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Date created: 6/5/2001 |
[ Dataplot ] |