Overview | Package | Class | Tree | Deprecated | Index | Help | Weka's home
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD

## weka.classifiers.trees.adtree
Class TwoWayNominalSplit

    java.lang.Object
      weka.classifiers.trees.adtree.Splitter
          weka.classifiers.trees.adtree.TwoWayNominalSplit

All Implemented Interfaces:
  java.io.Serializable, java.lang.Cloneable, RevisionHandler

    public class TwoWayNominalSplit

extends Splitter

Class representing a two-way split on a nominal attribute, of the form: either 'is some_value' or 'is not some_value'.

Version:
  $Revision: 1.6 $
Author:
  Richard Kirkby (rkirkby@cs.waikato.ac.nz)
See Also:
  Serialized Form

Field Summary

Fields inherited from class weka.classifiers.trees.adtree.Splitter
`orderAdded`

Constructor Summary
`TwoWayNominalSplit(int _attIndex, int _trueSplitValue)` Creates a new two-way nominal splitter.

Method Summary
`java.lang.String` | `attributeString(Instances dataset)` Gets the string describing the attributes the split depends on.
`int` | `branchInstanceGoesDown(Instance inst)` Gets the index of the branch that an instance applies to.
`java.lang.Object` | `clone()` Clones this node.
`java.lang.String` | `comparisonString(int branchNum, Instances dataset)` Gets the string describing the comparision the split depends on for a particular branch.
`boolean` | `equalTo(Splitter compare)` Tests whether two splitters are equivalent.
`PredictionNode` | `getChildForBranch(int branchNum)` Gets the child for a branch of the split.
`int` | `getNumOfBranches()` Gets the number of branches of the split.
`java.lang.String` | `getRevision()` Returns the revision string.
`ReferenceInstances` | `instancesDownBranch(int branch, Instances instances)` Gets the subset of instances that apply to a particluar branch of the split.
`void` | `setChildForBranch(int branchNum, PredictionNode childPredictor)` Sets the child for a branch of the split.

Methods inherited from class java.lang.Object
`equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### TwoWayNominalSplit

    public TwoWayNominalSplit(int _attIndex,
                              int _trueSplitValue)

  Creates a new two-way nominal splitter.

  Parameters:
    `_attIndex` - the index of the attribute this split depeneds on
    `_trueSplitValue` - the attribute value that the splitter splits on

Method Detail

### getNumOfBranches

    public int getNumOfBranches()

  Gets the number of branches of the split.

  Specified by:
    `getNumOfBranches` in class `Splitter`
  Returns:
    the number of branches (always = 2)

### branchInstanceGoesDown

    public int branchInstanceGoesDown(Instance inst)

  Gets the index of the branch that an instance applies to. Returns -1 if no branches apply.

  Specified by:
    `branchInstanceGoesDown` in class `Splitter`
  Parameters:
    `inst` - the instance
  Returns:
    the branch index

### instancesDownBranch

    public ReferenceInstances instancesDownBranch(int branch,
                                                  Instances instances)

  Gets the subset of instances that apply to a particluar branch of the split. If the branch index is -1, the subset will consist of those instances that don't apply to any branch.

  Specified by:
    `instancesDownBranch` in class `Splitter`
  Parameters:
    `branch` - the index of the branch
    `instances` - the instances from which to find the subset
  Returns:
    the set of instances that apply

### attributeString

    public java.lang.String attributeString(Instances dataset)

  Gets the string describing the attributes the split depends on. i.e. the left hand side of the description of the split.

  Specified by:
    `attributeString` in class `Splitter`
  Parameters:
    `dataset` - the dataset that the split is based on
  Returns:
    a string describing the attributes

### comparisonString

    public java.lang.String comparisonString(int branchNum,
                                             Instances dataset)

  Gets the string describing the comparision the split depends on for a particular branch. i.e. the right hand side of the description of the split.

  Specified by:
    `comparisonString` in class `Splitter`
  Parameters:
    `branchNum` - the branch of the split
    `dataset` - the dataset that the split is based on
  Returns:
    a string describing the comparison

### equalTo

    public boolean equalTo(Splitter compare)

  Tests whether two splitters are equivalent.

  Specified by:
    `equalTo` in class `Splitter`
  Parameters:
    `compare` - the splitter to compare with
  Returns:
    whether or not they match

### setChildForBranch

    public void setChildForBranch(int branchNum,
                                  PredictionNode childPredictor)

  Sets the child for a branch of the split.

  Specified by:
    `setChildForBranch` in class `Splitter`
  Parameters:
    `branchNum` - the branch to set the child for
    `childPredictor` - the new child

### getChildForBranch

    public PredictionNode getChildForBranch(int branchNum)

  Gets the child for a branch of the split.

  Specified by:
    `getChildForBranch` in class `Splitter`
  Parameters:
    `branchNum` - the branch to get the child for
  Returns:
    the child

### clone

    public java.lang.Object clone()

  Clones this node. Performs a deep copy, recursing through the tree.

  Specified by:
    `clone` in class `Splitter`
  Returns:
    a clone

### getRevision

    public java.lang.String getRevision()

  Returns the revision string.

  Returns:
    the revision

Overview | Package | Class | Tree | Deprecated | Index | Help | Weka's home
PREV CLASS NEXT CLASS | FRAMES NO FRAMES
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD