weka.clusterers

## Interface Clusterer

- All Known Subinterfaces:
    DensityBasedClusterer
  All Known Implementing Classes:
    AbstractClusterer, AbstractDensityBasedClusterer, Canopy, Cobweb, EM, FarthestFirst, FilteredClusterer, HierarchicalClusterer, MakeDensityBasedClusterer, RandomizableClusterer, RandomizableDensityBasedClusterer, RandomizableSingleClustererEnhancer, SimpleKMeans, SingleClustererEnhancer

      public interface Clusterer

  Interface for clusterers. Clients will typically extend either AbstractClusterer or AbstractDensityBasedClusterer.
  Version:
    $Revision: 8034 $
  Author:
    Mark Hall (mhall@cs.waikato.ac.nz)

- - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `buildClusterer(Instances data)` Generates a clusterer.
    `int` | `clusterInstance(Instance instance)` Classifies a given instance.
    `double[]` | `distributionForInstance(Instance instance)` Predicts the cluster memberships for a given instance.
    `Capabilities` | `getCapabilities()` Returns the Capabilities of this clusterer.
    `int` | `numberOfClusters()` Returns the number of clusters.

- - ### Method Detail

    - #### buildClusterer

          void buildClusterer(Instances data)
                              throws java.lang.Exception

      Generates a clusterer. Has to initialize all fields of the clusterer that are not being set via options.
      Parameters:
        `data` - set of instances serving as training data
      Throws:
        `java.lang.Exception` - if the clusterer has not been generated successfully

    - #### clusterInstance

          int clusterInstance(Instance instance)
                              throws java.lang.Exception

      Classifies a given instance. Either this or distributionForInstance() needs to be implemented by subclasses.
      Parameters:
        `instance` - the instance to be assigned to a cluster
      Returns:
        the number of the assigned cluster as an integer
      Throws:
        `java.lang.Exception` - if instance could not be clustered successfully

    - #### distributionForInstance

          double[] distributionForInstance(Instance instance)
                                           throws java.lang.Exception

      Predicts the cluster memberships for a given instance. Either this or clusterInstance() needs to be implemented by subclasses.
      Parameters:
        `instance` - the instance to be assigned a cluster.
      Returns:
        an array containing the estimated membership probabilities of the test instance in each cluster (this should sum to at most 1)
      Throws:
        `java.lang.Exception` - if distribution could not be computed successfully

    - #### numberOfClusters

          int numberOfClusters()
                               throws java.lang.Exception

      Returns the number of clusters.
      Returns:
        the number of clusters generated for a training dataset.
      Throws:
        `java.lang.Exception` - if number of clusters could not be returned successfully

    - #### getCapabilities

          Capabilities getCapabilities()

      Returns the Capabilities of this clusterer. Derived classifiers have to override this method to enable capabilities.
      Returns:
        the capabilities of this object
      See Also:
        `Capabilities`