Package cern.jet.stat.quantile

Class ExactDoubleQuantileFinder

  • All Implemented Interfaces:
    DoubleQuantileFinder, java.io.Serializable, java.lang.Cloneable
    class ExactDoubleQuantileFinder
extends PersistentObject
implements DoubleQuantileFinder
    Exact quantile finding algorithm for known and unknown N requiring large main memory; computes quantiles over a sequence of double elements. The folkore algorithm: Keeps all elements in main memory, sorts the list, then picks the quantiles.
    Version:
    1.0, 09/24/99

    • Constructor Summary

      Constructors 
      Constructor Description
      ExactDoubleQuantileFinder()
      Constructs an empty exact quantile finder.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void add​(double value)
      Adds a value to the receiver.
      void addAllOf​(DoubleArrayList values)
      Adds all values of the specified list to the receiver.
      void addAllOfFromTo​(DoubleArrayList values, int from, int to)
      Adds the part of the specified list between indexes from (inclusive) and to (inclusive) to the receiver.
      void clear()
      Removes all elements from the receiver.
      java.lang.Object clone()
      Returns a deep copy of the receiver.
      boolean contains​(double element)
      Returns whether the specified element is contained in the receiver.
      boolean forEach​(DoubleProcedure procedure)
      Applies a procedure to each element of the receiver, if any.
      long memory()
      Returns the number of elements currently needed to store all contained elements.
      double phi​(double element)
      Returns how many percent of the elements contained in the receiver are <= element.
      DoubleArrayList quantileElements​(DoubleArrayList phis)
      Computes the specified quantile elements over the values previously added.
      long size()
      Returns the number of elements currently contained in the receiver (identical to the number of values added so far).
      protected void sort()
      Sorts the receiver.
      java.lang.String toString()
      Returns a String representation of the receiver.
      long totalMemory()
      Returns the number of elements currently needed to store all contained elements.

      • Methods inherited from class java.lang.Object

        equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • isSorted

        protected boolean isSorted

    • Constructor Detail

      • ExactDoubleQuantileFinder

        public ExactDoubleQuantileFinder()
        Constructs an empty exact quantile finder.

    • Method Detail

      • add

        public void add​(double value)
        Adds a value to the receiver.
        Specified by:
        add in interface DoubleQuantileFinder
        Parameters:
        value - the value to add.

      • addAllOf

        public void addAllOf​(DoubleArrayList values)
        Adds all values of the specified list to the receiver.
        Specified by:
        addAllOf in interface DoubleQuantileFinder
        Parameters:
        values - the list of which all values shall be added.

      • addAllOfFromTo

        public void addAllOfFromTo​(DoubleArrayList values,
                           int from,
                           int to)
        Adds the part of the specified list between indexes from (inclusive) and to (inclusive) to the receiver.
        Specified by:
        addAllOfFromTo in interface DoubleQuantileFinder
        Parameters:
        values - the list of which elements shall be added.
        from - the index of the first element to be added (inclusive).
        to - the index of the last element to be added (inclusive).

      • clear

        public void clear()
        Removes all elements from the receiver. The receiver will be empty after this call returns, and its memory requirements will be close to zero.
        Specified by:
        clear in interface DoubleQuantileFinder

      • contains

        public boolean contains​(double element)
        Returns whether the specified element is contained in the receiver.

      • forEach

        public boolean forEach​(DoubleProcedure procedure)
        Applies a procedure to each element of the receiver, if any. Iterates over the receiver in no particular order.
        Specified by:
        forEach in interface DoubleQuantileFinder
        Parameters:
        procedure - the procedure to be applied. Stops iteration if the procedure returns false, otherwise continues.
        Returns:
        false if the procedure stopped before all elements where iterated over, true otherwise.

      • memory

        public long memory()
        Returns the number of elements currently needed to store all contained elements. This number usually differs from the results of method size(), according to the underlying datastructure.
        Specified by:
        memory in interface DoubleQuantileFinder

      • phi

        public double phi​(double element)
        Returns how many percent of the elements contained in the receiver are <= element. Does linear interpolation if the element is not contained but lies in between two contained elements.
        Specified by:
        phi in interface DoubleQuantileFinder
        Parameters:
        the - element to search for.
        Returns:
        the percentage p of elements <= element (0.0 <= p <=1.0).

      • quantileElements

        public DoubleArrayList quantileElements​(DoubleArrayList phis)
        Computes the specified quantile elements over the values previously added.
        Specified by:
        quantileElements in interface DoubleQuantileFinder
        Parameters:
        phis - the quantiles for which elements are to be computed. Each phi must be in the interval [0.0,1.0]. phis must be sorted ascending.
        Returns:
        the exact quantile elements.

      • size

        public long size()
        Returns the number of elements currently contained in the receiver (identical to the number of values added so far).
        Specified by:
        size in interface DoubleQuantileFinder

      • sort

        protected void sort()
        Sorts the receiver.

      • toString

        public java.lang.String toString()
        Returns a String representation of the receiver.
        Overrides:
        toString in class java.lang.Object

      • totalMemory

        public long totalMemory()
        Returns the number of elements currently needed to store all contained elements. This number usually differs from the results of method size(), according to the underlying datastructure.
        Specified by:
        totalMemory in interface DoubleQuantileFinder