org.dllearner.utilities.owl
Class DescriptionMinimizer

java.lang.Object
  org.dllearner.utilities.owl.DescriptionMinimizer

public class DescriptionMinimizer
extends Object

Rewrites a description to an equivalent shorter description. Note that minimizing is not a trivial operation and requires reasoning. The class keeps an internal cache on reasoning results, i.e. if similar descriptions are passed to the minimizer, then its performance will improve over time.

Author:

Jens Lehmann

Constructor Summary

DescriptionMinimizer(AbstractReasonerComponent reasoner)

Method Summary

Description	minimize(Description description) Same as minimizeClone(Description), but with no guarantee that the input description remains unmodified.
Description	minimizeClone(Description description) Method which minimzes the input description.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DescriptionMinimizer

public DescriptionMinimizer(AbstractReasonerComponent reasoner)

Method Detail

minimizeClone

public Description minimizeClone(Description description)

Method which minimzes the input description. The algorithm does not replace subdescriptions with named classes, e.g. if the description "male \sqcap \exists hasChild.\top" is passed to the algorithm and a class "father" is defined in the obvious way in the background knowledge, then it will intentionally not return father. Instead, it preserves the existing structure of the description, but tries to detect and delete redundant parts within it. For instance, the description "male \sqcap father" is minimized to "father".

Parameters:

description - The description to minimize.

Returns:

Minimized description.

minimize

public Description minimize(Description description)

Same as minimizeClone(Description), but with no guarantee that the input description remains unmodified.

Parameters:

description - The description to minimize.

Returns:

Minimized description.

See Also:

minimizeClone(Description)