com.yahoo.sketches.theta

Class PairwiseSetOperations

java.lang.Object

com.yahoo.sketches.theta.PairwiseSetOperations

public class PairwiseSetOperations
extends Object

Set Operations where the arguments are presented in pairs as in C = Op(A,B). These are stateless operations and the result is returned immediately. These operations are designed for high performance and only accept ordered, CompactSketches, which may be either Heap-based or Direct. The returned results are always in the form of an ordered CompactSketch.

Author:

Lee Rhodes

Constructor Summary

Constructors

Constructor and Description
PairwiseSetOperations()

Method Summary

Modifier and Type	Method and Description
static CompactSketch	aNotB(CompactSketch skA, CompactSketch skB) This implements a stateless, pair-wise A AND NOT B operation on ordered, CompactSketches that are either Heap-based or Direct.
static CompactSketch	intersect(CompactSketch skA, CompactSketch skB) This implements a stateless, pair-wise intersection operation on ordered, CompactSketches that are either Heap-based or Direct.
static CompactSketch	union(CompactSketch skA, CompactSketch skB) This implements a stateless, pair-wise union operation on ordered, CompactSketches that are either Heap-based or Direct.
static CompactSketch	union(CompactSketch skA, CompactSketch skB, int k) This implements a stateless, pair-wise union operation on ordered, CompactSketches that are either Heap-based or Direct.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PairwiseSetOperations

public PairwiseSetOperations()

Method Detail

intersect

public static CompactSketch intersect(CompactSketch skA,
                                      CompactSketch skB)

This implements a stateless, pair-wise intersection operation on ordered, CompactSketches that are either Heap-based or Direct. If both inputs are null a null is returned. If one is null an empty sketch is returned.

Parameters:

skA - The first ordered, CompactSketch argument.

skB - The second ordered, CompactSketch argument.

Returns:

the result as an ordered CompactSketch.

aNotB

public static CompactSketch aNotB(CompactSketch skA,
                                  CompactSketch skB)

This implements a stateless, pair-wise A AND NOT B operation on ordered, CompactSketches that are either Heap-based or Direct. If both inputs are null a null is returned. If skA is null an empty sketch is returned. If skB is null or empty skA is returned.

Parameters:

skA - The first ordered, CompactSketch argument.

skB - The second ordered, CompactSketch argument.

Returns:

the result as an ordered CompactSketch.

union

public static CompactSketch union(CompactSketch skA,
                                  CompactSketch skB)

This implements a stateless, pair-wise union operation on ordered, CompactSketches that are either Heap-based or Direct. If both inputs are null a null is returned. If one is null the other is returned, which can be either Heap-based or Direct. This is equivalent to union(skA, skB, k) where k is the default of 4096.

Parameters:

skA - The first ordered, CompactSketch argument.

skB - The second ordered, CompactSketch argument

Returns:

the result as an ordered CompactSketch.

union

public static CompactSketch union(CompactSketch skA,
                                  CompactSketch skB,
                                  int k)

This implements a stateless, pair-wise union operation on ordered, CompactSketches that are either Heap-based or Direct. If both inputs are null a null is returned. If one is null the other is returned, which can be either Heap-based or Direct.

Parameters:

skA - The first ordered, CompactSketch argument.

skB - The second ordered, CompactSketch argument

k - The upper bound of the number of entries to be retained by the sketch

Returns:

the result as an ordered CompactSketch.