weka.associations

## Class Item

- java.lang.Object
- - weka.associations.Item

- All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<Item>
  Direct Known Subclasses:
    NominalItem, NumericItem

      public abstract class Item
      extends java.lang.Object
      implements java.io.Serializable, java.lang.Comparable<Item>

  Class that encapsulates information about an individual item. An item is a value of a nominal attribute, so this class has a backing Attribute.
  Version:
    $Revision: 8034 $
  Author:
    Mark Hall (mhall{[at]}pentaho{[dot]}com).
  See Also:
    Serialized Form

- - ### Constructor Summary

    Constructors
    Constructor and Description
    `Item(Attribute att)`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `int` | `compareTo(Item comp)` Ensures that items will be sorted in descending order of frequency.
    `void` | `decreaseFrequency()` Decrement the frequency of this item.
    `void` | `decreaseFrequency(int f)` Decrease the frequency of this item.
    `boolean` | `equals(java.lang.Object compareTo)` Equals.
    `Attribute` | `getAttribute()` Get the attribute that this item originates from.
    `abstract java.lang.String` | `getComparisonAsString()` Get this item's comparison operator as a String.
    `int` | `getFrequency()` Get the frequency of this item.
    `abstract java.lang.String` | `getItemValueAsString()` Get this item's value as a String.
    `int` | `hashCode()`
    `void` | `increaseFrequency()` Increment the frequency of this item.
    `void` | `increaseFrequency(int f)` Increase the frequency of this item.
    `java.lang.String` | `toString()` A string representation of this item.
    `java.lang.String` | `toString(boolean freq)` A string representation of this item, (i.e.

    - ### Methods inherited from class java.lang.Object

      `getClass, notify, notifyAll, wait, wait, wait`

- - ### Constructor Detail

    - #### Item

          public Item(Attribute att)

  - ### Method Detail

    - #### increaseFrequency

          public void increaseFrequency(int f)

      Increase the frequency of this item.
      Parameters:
        `f` - the amount to increase the frequency by.

    - #### decreaseFrequency

          public void decreaseFrequency(int f)

      Decrease the frequency of this item.
      Parameters:
        `f` - the amount by which to decrease the frequency.

    - #### increaseFrequency

          public void increaseFrequency()

      Increment the frequency of this item.

    - #### decreaseFrequency

          public void decreaseFrequency()

      Decrement the frequency of this item.

    - #### getFrequency

          public int getFrequency()

      Get the frequency of this item.
      Returns:
        the frequency.

    - #### getAttribute

          public Attribute getAttribute()

      Get the attribute that this item originates from.
      Returns:
        the corresponding attribute.

    - #### getItemValueAsString

          public abstract java.lang.String getItemValueAsString()

      Get this item's value as a String.
      Returns:
        this item's value as a String.

    - #### getComparisonAsString

          public abstract java.lang.String getComparisonAsString()

      Get this item's comparison operator as a String.
      Returns:
        this item's comparison operator as a String.

    - #### toString

          public java.lang.String toString()

      A string representation of this item. (i.e. ).
      Overrides:
        `toString` in class `java.lang.Object`
      Returns:
        a string representation of this item.

    - #### toString

          public java.lang.String toString(boolean freq)

      A string representation of this item, (i.e. ). This default implementation just prints the attribute name and (optionally) frequency information.
      Parameters:
        `freq` - true if the frequency should be included.
      Returns:
        a string representation of this item.

    - #### compareTo

          public int compareTo(Item comp)

      Ensures that items will be sorted in descending order of frequency. Ties are ordered by attribute name.
      Specified by:
        `compareTo` in interface `java.lang.Comparable<Item>`
      Parameters:
        `comp` - the Item to compare against.

    - #### equals

          public boolean equals(java.lang.Object compareTo)

      Equals. Just compares attribute.
      Overrides:
        `equals` in class `java.lang.Object`
      Returns:
        true if this Item is equal to the argument.

    - #### hashCode

          public int hashCode()

      Overrides:
        `hashCode` in class `java.lang.Object`