weka.classifiers.rules

## Class Rule

- java.lang.Object
- - weka.classifiers.rules.Rule

- All Implemented Interfaces:
    java.io.Serializable, Copyable, RevisionHandler, WeightedInstancesHandler
  Direct Known Subclasses:
    JRip.RipperRule

      public abstract class Rule
      extends java.lang.Object
      implements WeightedInstancesHandler, Copyable, java.io.Serializable, RevisionHandler

  Abstract class of generic rule
  Version:
    $Revision: 8034 $
  Author:
    Xin Xu (xx5@cs.waikato.ac.nz)
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `Rule()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `java.lang.Object` | `copy()` Get a shallow copy of this rule
    `abstract boolean` | `covers(Instance datum)` Whether the instance covered by this rule
    `abstract double` | `getConsequent()` Get the consequent of this rule, i.e.
    `abstract void` | `grow(Instances data)` Build this rule
    `abstract boolean` | `hasAntds()` Whether this rule has antecedents, i.e.
    `abstract double` | `size()` The size of the rule.

    - ### Methods inherited from class java.lang.Object

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

    - ### Methods inherited from interface weka.core.RevisionHandler

      `getRevision`

- - ### Constructor Detail

    - #### Rule

          public Rule()

  - ### Method Detail

    - #### copy

          public java.lang.Object copy()

      Get a shallow copy of this rule
      Specified by:
        `copy` in interface `Copyable`
      Returns:
        the copy

    - #### covers

          public abstract boolean covers(Instance datum)

      Whether the instance covered by this rule
      Parameters:
        `datum` - the instance in question
      Returns:
        the boolean value indicating whether the instance is covered by this rule

    - #### grow

          public abstract void grow(Instances data)
                             throws java.lang.Exception

      Build this rule
      Parameters:
        `data` - the data used to build the rule
      Throws:
        `java.lang.Exception` - if rule cannot be built

    - #### hasAntds

          public abstract boolean hasAntds()

      Whether this rule has antecedents, i.e. whether it is a default rule
      Returns:
        the boolean value indicating whether the rule has antecedents

    - #### getConsequent

          public abstract double getConsequent()

      Get the consequent of this rule, i.e. the predicted class
      Returns:
        the consequent

    - #### size

          public abstract double size()

      The size of the rule. Could be number of antecedents in the case of conjunctive rule
      Returns:
        the size of the rule