Class Frequency

java.lang.Object
org.apache.commons.math.stat.Frequency
All Implemented Interfaces:
Serializable

public class Frequency extends Object implements Serializable
Maintains a frequency distribution.

Accepts int, long, char or Comparable values. New values added must be comparable to those that have been added, otherwise the add method will throw an IllegalArgumentException.

Integer values (int, long, Integer, Long) are not distinguished by type -- i.e. addValue(Long.valueOf(2)), addValue(2), addValue(2l) all have the same effect (similarly for arguments to getCount, etc.).

char values are converted by addValue to Character instances. As such, these values are not comparable to integral values, so attempts to combine integral types with chars in a frequency distribution will fail.

The values are ordered using the default (natural order), unless a Comparator is supplied in the constructor.

Version:
$Revision: 1054186 $ $Date: 2011-01-01 03:28:46 +0100 (sam. 01 janv. 2011) $
See Also:
  • Constructor Summary

    Constructors
    Constructor
    Description
    Default constructor.
    Frequency(Comparator<?> comparator)
    Constructor allowing values Comparator to be specified.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    addValue(char v)
    Adds 1 to the frequency count for v.
    void
    addValue(int v)
    Adds 1 to the frequency count for v.
    void
    addValue(long v)
    Adds 1 to the frequency count for v.
    void
    Adds 1 to the frequency count for v.
    void
    Deprecated.
    to be removed in math 3.0
    void
    Deprecated.
    void
    Clears the frequency table
    boolean
    long
    getCount(char v)
    Returns the number of values = v.
    long
    getCount(int v)
    Returns the number of values = v.
    long
    getCount(long v)
    Returns the number of values = v.
    long
    Returns the number of values = v.
    long
    Deprecated.
    replaced by getCount(Comparable) as of 2.0
    long
    getCumFreq(char v)
    Returns the cumulative frequency of values less than or equal to v.
    long
    getCumFreq(int v)
    Returns the cumulative frequency of values less than or equal to v.
    long
    getCumFreq(long v)
    Returns the cumulative frequency of values less than or equal to v.
    long
    Returns the cumulative frequency of values less than or equal to v.
    long
    Deprecated.
    replaced by getCumFreq(Comparable) as of 2.0
    double
    getCumPct(char v)
    Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).
    double
    getCumPct(int v)
    Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).
    double
    getCumPct(long v)
    Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).
    double
    Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).
    double
    Deprecated.
    replaced by getCumPct(Comparable) as of 2.0
    double
    getPct(char v)
    Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
    double
    getPct(int v)
    Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
    double
    getPct(long v)
    Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
    double
    Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
    double
    Deprecated.
    replaced by getPct(Comparable) as of 2.0
    long
    Returns the sum of all frequencies.
    int
    Returns the number of values in the frequency table.
    int
    Return a string representation of this frequency distribution.
    Returns an Iterator over the set of values that have been added.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait
  • Constructor Details

    • Frequency

      public Frequency()
      Default constructor.
    • Frequency

      public Frequency(Comparator<?> comparator)
      Constructor allowing values Comparator to be specified.
      Parameters:
      comparator - Comparator used to order values
  • Method Details

    • toString

      public String toString()
      Return a string representation of this frequency distribution.
      Overrides:
      toString in class Object
      Returns:
      a string representation.
    • addValue

      @Deprecated public void addValue(Object v)
      Deprecated.
      Adds 1 to the frequency count for v.

      If other objects have already been added to this Frequency, v must be comparable to those that have already been added.

      Parameters:
      v - the value to add.
      Throws:
      IllegalArgumentException - if v is not Comparable, or is not comparable with previous entries
    • addValue

      public void addValue(Comparable<?> v)
      Adds 1 to the frequency count for v.

      If other objects have already been added to this Frequency, v must be comparable to those that have already been added.

      Parameters:
      v - the value to add.
      Throws:
      IllegalArgumentException - if v is not comparable with previous entries
    • addValue

      public void addValue(int v)
      Adds 1 to the frequency count for v.
      Parameters:
      v - the value to add.
    • addValue

      @Deprecated public void addValue(Integer v)
      Deprecated.
      to be removed in math 3.0
      Adds 1 to the frequency count for v.
      Parameters:
      v - the value to add.
    • addValue

      public void addValue(long v)
      Adds 1 to the frequency count for v.
      Parameters:
      v - the value to add.
    • addValue

      public void addValue(char v)
      Adds 1 to the frequency count for v.
      Parameters:
      v - the value to add.
    • clear

      public void clear()
      Clears the frequency table
    • valuesIterator

      public Iterator<Comparable<?>> valuesIterator()
      Returns an Iterator over the set of values that have been added.

      If added values are integral (i.e., integers, longs, Integers, or Longs), they are converted to Longs when they are added, so the objects returned by the Iterator will in this case be Longs.

      Returns:
      values Iterator
    • getSumFreq

      public long getSumFreq()
      Returns the sum of all frequencies.
      Returns:
      the total frequency count.
    • getCount

      @Deprecated public long getCount(Object v)
      Deprecated.
      replaced by getCount(Comparable) as of 2.0
      Returns the number of values = v. Returns 0 if the value is not comparable.
      Parameters:
      v - the value to lookup.
      Returns:
      the frequency of v.
    • getCount

      public long getCount(Comparable<?> v)
      Returns the number of values = v. Returns 0 if the value is not comparable.
      Parameters:
      v - the value to lookup.
      Returns:
      the frequency of v.
    • getCount

      public long getCount(int v)
      Returns the number of values = v.
      Parameters:
      v - the value to lookup.
      Returns:
      the frequency of v.
    • getCount

      public long getCount(long v)
      Returns the number of values = v.
      Parameters:
      v - the value to lookup.
      Returns:
      the frequency of v.
    • getCount

      public long getCount(char v)
      Returns the number of values = v.
      Parameters:
      v - the value to lookup.
      Returns:
      the frequency of v.
    • getUniqueCount

      public int getUniqueCount()
      Returns the number of values in the frequency table.
      Returns:
      the number of unique values that have been added to the frequency table.
      See Also:
    • getPct

      @Deprecated public double getPct(Object v)
      Deprecated.
      replaced by getPct(Comparable) as of 2.0
      Returns the percentage of values that are equal to v (as a proportion between 0 and 1).

      Returns Double.NaN if no values have been added.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getPct

      public double getPct(Comparable<?> v)
      Returns the percentage of values that are equal to v (as a proportion between 0 and 1).

      Returns Double.NaN if no values have been added.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getPct

      public double getPct(int v)
      Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getPct

      public double getPct(long v)
      Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getPct

      public double getPct(char v)
      Returns the percentage of values that are equal to v (as a proportion between 0 and 1).
      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getCumFreq

      @Deprecated public long getCumFreq(Object v)
      Deprecated.
      replaced by getCumFreq(Comparable) as of 2.0
      Returns the cumulative frequency of values less than or equal to v.

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup.
      Returns:
      the proportion of values equal to v
    • getCumFreq

      public long getCumFreq(Comparable<?> v)
      Returns the cumulative frequency of values less than or equal to v.

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup.
      Returns:
      the proportion of values equal to v
    • getCumFreq

      public long getCumFreq(int v)
      Returns the cumulative frequency of values less than or equal to v.

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getCumFreq

      public long getCumFreq(long v)
      Returns the cumulative frequency of values less than or equal to v.

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getCumFreq

      public long getCumFreq(char v)
      Returns the cumulative frequency of values less than or equal to v.

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values equal to v
    • getCumPct

      @Deprecated public double getCumPct(Object v)
      Deprecated.
      replaced by getCumPct(Comparable) as of 2.0
      Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).

      Returns Double.NaN if no values have been added. Returns 0 if at least one value has been added, but v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values less than or equal to v
    • getCumPct

      public double getCumPct(Comparable<?> v)
      Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).

      Returns Double.NaN if no values have been added. Returns 0 if at least one value has been added, but v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values less than or equal to v
    • getCumPct

      public double getCumPct(int v)
      Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values less than or equal to v
    • getCumPct

      public double getCumPct(long v)
      Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values less than or equal to v
    • getCumPct

      public double getCumPct(char v)
      Returns the cumulative percentage of values less than or equal to v (as a proportion between 0 and 1).

      Returns 0 if v is not comparable to the values set.

      Parameters:
      v - the value to lookup
      Returns:
      the proportion of values less than or equal to v
    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object
    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object