java.lang.Object
- com.pervasive.datarush.analytics.arm.ItemSet

All Implemented Interfaces:

Serializable
```
public class ItemSet
extends Object
implements Serializable
```
A representation of a set of items with their support (frequency) within a data set. Items are represented by int values. It is assumed that each item has a distinct integer identifier.
The necessary methods are implemented allowing instances of this class to be used within the standard utility library (i.e. HashMap ...).

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor	Description
`ItemSet(int itemID)`	Construct an item set with a single item.
`ItemSet(int[] itemIDs)`	Construct an item set from the given items.
`ItemSet(int[] itemIDs, int length)`	Create an item set from the list of items specifying how many from the list to use.
`ItemSet(int[] itemsLHS, int[] itemsRHS)`	Combine the two sets of items into one set.
`ItemSet(int[] itemIDs, long support, double supportPct)`	Construct an item set from the given items.
`ItemSet(int itemID, int[] itemIDs)`	Combine the given singular item and a list of items into a single item set.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`calculateSupportPct(long transactionTotal)`	Given the number of transactions in a DB compute the support percent for this item set.
`boolean`	`equals(Object o)`
`int[]`	`getItemIDs()`	Get the item identifiers contained in this item list.
`long`	`getSupport()`	Get the current support value.
`double`	`getSupportPct()`	Get the support percentage value.
`int`	`hashCode()`
`void`	`incrementSupport()`	Increment the support value.
`static Comparator<ItemSet>`	`newSetSizeComparator()`	Create a new `Comparator` that compares item sets and allows sorting by item set size and support.
`boolean`	`represents(int[] items)`	Returns whether the given list of items matches the list of items within this item set.
`void`	`setSupport(long support)`	Set the support value.
`int`	`size()`	Return the size of this item set.
`String`	`toString()`

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

- Constructor Detail
  - ItemSet
```
public ItemSet(int itemID)
```
    Construct an item set with a single item.
    
    Parameters:
    
    itemID - item identifier
  - ItemSet
```
public ItemSet(int[] itemIDs)
```
    Construct an item set from the given items. Assume ownership of the array.
    
    Parameters:
    
    itemIDs - items within the item set
  - ItemSet
```
public ItemSet(int[] itemIDs,
               long support,
               double supportPct)
```
    Construct an item set from the given items. Assume ownership of the array. Use the given support values for initial values.
    
    Parameters:
    
    itemIDs - items within the item set
    
    support - the initial support value
    
    supportPct - the initial support percentage value
  - ItemSet
```
public ItemSet(int itemID,
               int[] itemIDs)
```
    Combine the given singular item and a list of items into a single item set.
    
    Parameters:
    
    itemID - the singular item
    
    itemIDs - a list of items
  - ItemSet
```
public ItemSet(int[] itemsLHS,
               int[] itemsRHS)
```
    Combine the two sets of items into one set.
    
    Parameters:
    
    itemsLHS - a list of item identifiers
    
    itemsRHS - a list of item identifiers
  - ItemSet
```
public ItemSet(int[] itemIDs,
               int length)
```
    Create an item set from the list of items specifying how many from the list to use.
    
    Parameters:
    
    itemIDs - the item identifiers
    
    length - the number of items to include
- Method Detail
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - represents
```
public boolean represents(int[] items)
```
    Returns whether the given list of items matches the list of items within this item set.
    
    Parameters:
    
    items - item identifiers
    
    Returns:
    
    true if all items match, false otherwise
  - size
```
public int size()
```
    Return the size of this item set.
    
    Returns:
    
    the size of the item set
  - getItemIDs
```
public int[] getItemIDs()
```
    Get the item identifiers contained in this item list.
    
    Returns:
    
    list of item identifiers
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - calculateSupportPct
```
public void calculateSupportPct(long transactionTotal)
```
    Given the number of transactions in a DB compute the support percent for this item set.
    
    Parameters:
    
    transactionTotal - total number of transactions
  - getSupportPct
```
public double getSupportPct()
```
    Get the support percentage value.
    
    Returns:
    
    support percentage (support / transaction count)
  - incrementSupport
```
public void incrementSupport()
```
    Increment the support value.
  - getSupport
```
public long getSupport()
```
    Get the current support value.
    
    Returns:
    
    support value
  - setSupport
```
public void setSupport(long support)
```
    Set the support value.
    
    Parameters:
    
    support - support value to set
  - newSetSizeComparator
```
public static Comparator<ItemSet> newSetSizeComparator()
```
    Create a new Comparator that compares item sets and allows sorting by item set size and support.
    
    Returns:
    
    a new Comparator instance

Class ItemSet

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ItemSet

ItemSet

ItemSet

ItemSet

ItemSet

ItemSet

Method Detail

equals

hashCode

represents

size

getItemIDs

toString

calculateSupportPct

getSupportPct

incrementSupport

getSupport

setSupport

newSetSizeComparator