KthSelector (Apache Commons Math 3.6.1 API)

java.lang.Object

org.apache.commons.math3.util.KthSelector

All Implemented Interfaces:: Serializable

public class KthSelector extends Object implements Serializable

A Simple K^th selector implementation to pick up the K^th ordered element from a work array containing the input numbers.

Since:

3.4

See Also:

Constructor Summary

Constructors

Constructor

Description

KthSelector()

Constructor with default median of 3 pivoting strategy

KthSelector(PivotingStrategyInterface pivotingStrategy)

Constructor with specified pivoting strategy
Method Summary

Modifier and Type

Method

Description

PivotingStrategyInterface

getPivotingStrategy()

Get the pivotin strategy.

double

select(double[] work, int[] pivotsHeap, int k)

Select K^th value in the array.

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

Constructor Details
- KthSelector
  
  public KthSelector()
  
  Constructor with default median of 3 pivoting strategy
- KthSelector
  
  public KthSelector(PivotingStrategyInterface pivotingStrategy) throws NullArgumentException
  
  Constructor with specified pivoting strategy
  Parameters:
  
  pivotingStrategy - pivoting strategy to use
  
  Throws:
  
  NullArgumentException - when pivotingStrategy is null
  
  See Also:
  
  MedianOf3PivotingStrategy
  
  RandomPivotingStrategy
  
  CentralPivotingStrategy
Method Details
- getPivotingStrategy
  
  public PivotingStrategyInterface getPivotingStrategy()
  
  Get the pivotin strategy.
  
  Returns:
  
  pivoting strategy
- select
  
  public double select(double[] work, int[] pivotsHeap, int k)
  
  Select K^th value in the array.
  
  Parameters:
  
  work - work array to use to find out the K^th value
  
  pivotsHeap - cached pivots heap that can be used for efficient estimation
  
  k - the index whose value in the array is of interest
  
  Returns:
  
  K^th value