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clustering

This example is only supported when using XVM (with its jni plug-in installed), SWI-Prolog, or YAP as the backend compiler.

This is a simple example of using a Java library for performing clustering of a set of numbers. It uses the Apache Commons Math Java library, which you must download from:

https://commons.apache.org/proper/commons-math/

After downloading the library archive, decompress it, and copy the main JAR (for version 3.6.1, this would be the commons-math3-3.6.1.jar file) to this example jars folder before running the example.

Be sure to have download the required JAR files before attempting to run this example; see the NOTES.txt file for details

Running from a terminal

When running this example from the terminal (i.e., not as a notebook), start by setting the Java CLASSPATH environment variable. Three backend Prolog systems are supported: XVM, SWI-Prolog, and YAP. There's a Bash script file that sets the CLASSPATH environment variable when sourced:

$ cd "$LOGTALKUSER/examples/document_converter"
$ . set_classpath.sh

Similar for Windows using the set_classpath.ps1 PowerShell script.

Running as a notebook

Print Logtalk, Prolog backend, and kernel versions (if running as a notebook):

%versions

Set the required environment variables (edit if using a different Apache Commons Math version):

setenv('CLASSPATH', './jars/commons-math3-3.6.1.jar').

Load the example:

logtalk_load(clustering(loader)).

Create 4 clusters from a list of float values:

clustering::clusters([1.0,1.5,1.8,3.5,3.6,4.0,4.2], 4, 10000, Clusters).