de.lmu.ifi.dbs.elki.algorithm.itemsetmining

Class DenseItemset

java.lang.Object

de.lmu.ifi.dbs.elki.algorithm.itemsetmining.Itemset

de.lmu.ifi.dbs.elki.algorithm.itemsetmining.DenseItemset

All Implemented Interfaces:

java.lang.Comparable<Itemset>

public class DenseItemset
extends Itemset

APRIORI itemset, dense representation.

Since:

0.7.0

Author:

Erich Schubert

Field Summary

Fields

Modifier and Type	Field and Description
(package private) long[]	items Items, as a bitmask.
(package private) int	length Itemset length.

Fields inherited from class de.lmu.ifi.dbs.elki.algorithm.itemsetmining.Itemset

support

Constructor Summary

Constructors

Constructor and Description
DenseItemset(long[] items, int length) Constructor.

Method Summary

Modifier and Type	Method and Description
java.lang.StringBuilder	appendItemsTo(java.lang.StringBuilder buf, VectorFieldTypeInformation<BitVector> meta) Only append the items to a string buffer.
int	compareTo(Itemset o)
boolean	containedIn(SparseNumberVector bv) Test whether the itemset is contained in a bit vector.
boolean	equals(java.lang.Object obj)
int	hashCode() Deprecated. Itemsets MUST NOT BE USED IN HASH MAPS.
int	iter() Get an iterator over items, usually the position within an array.
int	iterAdvance(int iter) Advance the iterator to the next position.
int	iterDim(int iter) Item at the iterator position.
boolean	iterValid(int iter) Check if the iterator position is valid.
int	length() Itemset length.

Methods inherited from class de.lmu.ifi.dbs.elki.algorithm.itemsetmining.Itemset

appendTo, compareLexicographical, getSupport, increaseSupport, toBitset, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

items

long[] items

Items, as a bitmask.

length

int length

Itemset length.

Constructor Detail

DenseItemset

public DenseItemset(long[] items,
                    int length)

Constructor.

Parameters:

items - Items

length - Length (Cardinality of itemset)

Method Detail

length

public int length()

Description copied from class: Itemset

Itemset length.

Specified by:

length in class Itemset

Returns:

Itemset length

containedIn

public boolean containedIn(SparseNumberVector bv)

Description copied from class: Itemset

Test whether the itemset is contained in a bit vector.

Overrides:

containedIn in class Itemset

Parameters:

bv - Bit vector

Returns:

true when the itemset is contained in this vector.

iter

public int iter()

Description copied from class: Itemset

Get an iterator over items, usually the position within an array. Intended usage:

 
 for (int iter = v.iter(); v.iterValid(iter); iter = v.iterAdvance(iter)) {
   final int item = v.iterItem(iter);
   // Do something.
 }
 
 

Specified by:

iter in class Itemset

Returns:

Iterator

iterValid

public boolean iterValid(int iter)

Description copied from class: Itemset

Check if the iterator position is valid.

Specified by:

iterValid in class Itemset

Parameters:

iter - Iterator

Returns:

true if the position is valid.

iterAdvance

public int iterAdvance(int iter)

Description copied from class: Itemset

Advance the iterator to the next position.

Specified by:

iterAdvance in class Itemset

Parameters:

iter - Iterator

Returns:

New iterator position

iterDim

public int iterDim(int iter)

Description copied from class: Itemset

Item at the iterator position.

Specified by:

iterDim in class Itemset

Parameters:

iter - Iterator

Returns:

Current item

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class Itemset

hashCode

@Deprecated
public int hashCode()

Deprecated. Itemsets MUST NOT BE USED IN HASH MAPS.

Overrides:

hashCode in class Itemset

compareTo

public int compareTo(Itemset o)

Specified by:

compareTo in interface java.lang.Comparable<Itemset>

Overrides:

compareTo in class Itemset

appendItemsTo

public java.lang.StringBuilder appendItemsTo(java.lang.StringBuilder buf,
                                             VectorFieldTypeInformation<BitVector> meta)

Description copied from class: Itemset

Only append the items to a string buffer.

Overrides:

appendItemsTo in class Itemset

Parameters:

buf - Buffer

meta - Relation metadata (for labels)

Returns:

String buffer for chaining.