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Pack logicmoo_cg -- test/prologPlusCG/README.txt

README for Prolog+CG Ulrik Petersen Last update: June 22, 2005

What is this?

Prolog+CG is a Java implementation of Prolog, with extensions for supporting conceptual graphs and Object Orientation.



That is also where you can get the sourcecode for Prolog+CG, among other goodies.

A better version is available

Prof. Adil Kabbaj, the original author of Prolog+CG, has developing a newer, better version Prolog+CG. It has been as part of the Amine platform:


How do I install it?

First, you need Java 1.4 or 1.5. If you don't have it, download it from




You need either the Java Runtime Environment (JRE) or the Java SDK. It should be version 1.4.2 or later.

Second, just unzip the file anywhere you your harddrive. Then look in the next section for how to run it.

Be sure to preserve the directory structure, which most modern ZIP programs do by default.

You can move the program directory around, so long as you move all files at once. There are no Windows Registry settings -- this is a cross-platform Java program.

How do I get it to run?

You must run java like this:

java -classpath classes PrologPlusCG/PrologPlusCG

You need Java 1.4.2 or later.

Make sure the current working directory is the one where this README file is found.

Windows users

For Windows users, there is a sample start.bat file which contains the above command. You must edit it and insert the path to your java.exe file.

Thus if java.exe is in C:\j2sdk\bin you must edit the start.bat file to say:

C:\j2sdk\bin\java.exe -classpath classes PrologPlusCG/PrologPlusCG

Note that you cannot use the java.exe file that comes with Internet Explorer. This is typically located in C:\Windows or C:\Windows\System or similar. Do not use this java.exe file!

If there is a space in the path, you must enclose the path + program in "double quotes". For example:

"C:\Program Files\JRE\1.4.2\bin\java.exe" -classpath classes PrologPlusCG/PrologPlusCG


Prolog+CG is made available under the licenses described in COPYING. Please read that file.


This distribution

  • NEWS: Release notes.
  • AUTHORS: Who wrote what, and how to contact the maintainer.
  • COPYING: Copyright and what license restrictions apply (not many!)
  • README: This file

Main website

The main Prolog+CG website is here:



The manual is included with the program, and will be displayed if you select the "Help" menu and select "PROLOG+CG user's manual". It is located in:


It is also available as PDF:


The manual is also available from the main website.



A tutorial on Prolog+CG, including a basic introduction to Prolog, is available here:


Use Module II.

Building from source

The Java compiler is invoked like this, in the root directory of the distribution:

javac -source 1.4 -target 1.4 -d classes -classpath classes -sourcepath src src/PrologPlusCG/PrologPlusCG.java

Note that the directory "classes" must exist. See the javac documentation for further pointers to what all the switches mean.

Then you must copy the src/PrologPlusCG/gui/ImgPrlg.png file to classes/PrologPlusCG/gui/ for this and the rest of the images to be displayed.