org.pentaho.aggdes.util

Class BitSetPlus

java.lang.Object

java.util.BitSet

org.pentaho.aggdes.util.BitSetPlus

All Implemented Interfaces:

Serializable, Cloneable

public class BitSetPlus
extends BitSet

Extension to BitSet.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
BitSetPlus()
BitSetPlus(int bitCount)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	contains(BitSet bitSet) Returns true if every bit in this set is also set in bitSet.
BigInteger	countSupersetDiff(List<BitSetPlus> minusBitSets) Returns the number of bitsets which are supersets of this BitSetPlus but which are not supersets of any of the sets in minusBitSets.
static BigInteger	countSupersetIntersection_old(int bitCount, BitSetPlus[] bitSets) Returns the number of sets which are supersets of at least one of the members of bitSets.
static BigInteger	countSupersetIntersection(int bitCount, BitSetPlus[] bitSets) Returns the number of sets which are supersets of every member of bitSets.
int	getBitCount()
BigInteger	supersetCardinality() Returns the number of bitsets which are supersets of bitSet.

Methods inherited from class java.util.BitSet

and, andNot, cardinality, clear, clear, clear, clone, equals, flip, flip, get, get, hashCode, intersects, isEmpty, length, nextClearBit, nextSetBit, or, previousClearBit, previousSetBit, set, set, set, set, size, toByteArray, toLongArray, toString, valueOf, valueOf, valueOf, valueOf, xor

Methods inherited from class java.lang.Object

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

Constructor Detail

BitSetPlus

public BitSetPlus()

BitSetPlus

public BitSetPlus(int bitCount)

Method Detail

getBitCount

public int getBitCount()

supersetCardinality

public BigInteger supersetCardinality()

Returns the number of bitsets which are supersets of bitSet.

For example, supersetCardinality(4, {0, 1, 1, 0}) is 4, because the supersets are {{0, 1, 1, 0}, {0, 1, 1, 1}, {1, 1, 1, 0}, {1, 1, 1, 1}}.

The formula is 2 ^ number of zero bits.

Returns:

the number of bitsets which are supersets of bitSet (including the bitset itself and the full set).

countSupersetDiff

public BigInteger countSupersetDiff(List<BitSetPlus> minusBitSets)

Returns the number of bitsets which are supersets of this BitSetPlus but which are not supersets of any of the sets in minusBitSets.

This method takes time and space exponential in the cardinality of minusBitSets.

Parameters:

minusBitSets - List of bit sets to subtract

Returns:

Cardinality

contains

public boolean contains(BitSet bitSet)

Returns true if every bit in this set is also set in bitSet.

countSupersetIntersection_old

public static BigInteger countSupersetIntersection_old(int bitCount,
                                       BitSetPlus[] bitSets)

Returns the number of sets which are supersets of at least one of the members of bitSets.

Example 1. Consider bitset0 = {0, 1, 1, 0}, bitset1 = {1, 0, 1, 1}. The supersets look like {0 or 1, 0 or 1, 1, 0 or 1}.

Parameters:

bitCount - Number of bits in each bitset

bitSets - List of bitsets

Returns:

Number of sets in superset

countSupersetIntersection

public static BigInteger countSupersetIntersection(int bitCount,
                                   BitSetPlus[] bitSets)

Returns the number of sets which are supersets of every member of bitSets.

Example 1. Consider bitset0 = {0, 1, 1, 0}, bitset1 = {1, 0, 1, 1}. The supersets look like {0 or 1, 0 or 1, 1, 0 or 1}.

Parameters:

bitCount - Number of bits in each bitset

bitSets - List of bitsets

Returns:

Number of sets in superset