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**                                                              **
**             IBM-PC Installation of DISGCL                    **
**                                                              **
**  Contents:  1.)  Introduction                                **
**             2.)  Installation of DISGCL                      **
**             3.)  Using Super VGA Cards                       **
**             4.)  Getting DISLIN Support                      **
**                                                              **
**  Date   :   15.03.2022                                       **
**  Version:   11.5    /  MS-DOS                                **
**  Author :   Helmut Michels                                   **
**             Dislin Software                                  **
**             Am Hachweg 10                                    **
**             37083 Göttingen, Germany                         **
**  Email  :   michels@dislin.de                                **
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1.)  Introduction
   
     This file describes the installation of the  graphics command
     language DISGCL which is an interpreter based on the graphics
     software DISLIN.  All  DISLIN  statements can be written to a
     script file and then be executed with  DISGCL,  or can be en-
     tered in an interactive mode.

     Similar to programming languages such as Fortran and C, high-
     level language elements can be used within DISGCL.  These are
     variables,  operators,  expressions, array operations, loops, 
     if and switch statements,  user-defined subroutines and func-
     tions, and file I/O routines.

     An easy to use  interface  for data input is given to include
     data into  DISGCL  jobs.  The format  of data  files  is very 
     simple and useful for most DISLIN plotting routines.

     Several quickplots are offered by  DISGCL which are collecti-
     ons of DISLIN statements to display data with one command.


2.)  Installation of DISGCL

     The  MS-DOS version of DISGCL is distributed as a  .zip  file 
     created with the file packaging utility ZIP (version 1.9).
     The .zip file has the file name  GCL_nn.ZIP  where  nn is the
     current version number  of DISGCL. A  utility for  unpacking
     the  DISLIN  files is available from the same location where
     you have downloaded GCL_nn.ZIP, or from the DISLIN CD-ROM. 

     To install DISGCL, make the following steps:

  a) Create a temporary directory and copy the files gcl_11.zip
     and unzip.exe to it:

     for example:   md  c:\temp
                    cd  c:\temp
                    copy e:\dislin\msdos\unzip.exe    *.*
                    copy e:\dislin\msdos\gcl_11.zip *.*
                    copy a:\*.*  *.*

  b) Extract DISGCL files with the command:

                    unzip -o gcl_11

  c) Run the install program with the command

                    INSTALL c:   (or INSTALL d:)

     The program INSTALL installs DISGCL in the directory 
     c:\DISLIN (or d:\DISLIN).

  d) Reconfigure the System

     Set the DISLIN environment variable to c:\dislin and include
     c:\dislin\djgpp in your path. If you have installed DISLIN in a
     different directory, you have to use that directory for the 
     environment variables above.

     The environment variables can be set or modified with the Control
     Panel 
    
     (see Control Panel -> System -> Advanced -> Environment
      Variables).

  e) Check the installation by running the examples

     Type:    disgcl  curve
       or:    disgcl  surface
       or:    disgcl  pie
       or:    disgcl  bars
       or:    disgcl  world
       or:    disgcl  contour

     The examples can be found in the directory:  \dislin\gcl


3.)  Using Super VGA Cards

     DISLIN uses by default BIOS calls to display graphics on the
     screen.  Special graphic modes can be defined with the 
     utility program  DISVID (see DISVID). This method is not very
     fast.
     
     To get fast graphical output on the screen, you can use the 
     interface of DISLIN to the GRX library of the DJGPP distribution.
     DISGCL is linked with the GRX library. All you have to do is to 
     set the environment variable GRX20DRV.

     For example: set GRX20DRV=VESA gw 1024 gh 768 nc 16m

     The GRX library is available from the site http://grx.gnu.de


3.)  Getting DISLIN Support

     The DISLIN distributions can be used freely without any restriction.
     Access to the source code is availabe via a support contract from the
     site www.dislin.de.


