org.apache.spark.mllib.tree.impurity
Class Gini

Object
  extended by org.apache.spark.mllib.tree.impurity.Gini
All Implemented Interfaces:
java.io.Serializable, Impurity

public class Gini
extends Object
implements Impurity

:: Experimental :: Class for calculating the Gini impurity during binary classification.

See Also:
Serialized Form

Constructor Summary
Gini()
           
 
Method Summary
static double calculate(double[] counts, double totalCount)
          :: DeveloperApi :: information calculation for multiclass classification
static double calculate(double count, double sum, double sumSquares)
          :: DeveloperApi :: variance calculation
static org.apache.spark.mllib.tree.impurity.Gini$ instance()
          Get this impurity instance.
 
Methods inherited from class Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.spark.mllib.tree.impurity.Impurity
calculate, calculate
 

Constructor Detail

Gini

public Gini()
Method Detail

calculate

public static double calculate(double[] counts,
                               double totalCount)
:: DeveloperApi :: information calculation for multiclass classification

Parameters:
counts - Array[Double] with counts for each label
totalCount - sum of counts for all labels
Returns:
information value, or 0 if totalCount = 0

calculate

public static double calculate(double count,
                               double sum,
                               double sumSquares)
:: DeveloperApi :: variance calculation

Parameters:
count - number of instances
sum - sum of labels
sumSquares - summation of squares of the labels
Returns:
information value, or 0 if count = 0

instance

public static org.apache.spark.mllib.tree.impurity.Gini$ instance()
Get this impurity instance. This is useful for passing impurity parameters to a Strategy in Java.

Returns:
(undocumented)