com.yahoo.sketches.theta

Class Sketches

java.lang.Object

com.yahoo.sketches.theta.Sketches

public final class Sketches
extends Object

This class brings together the common sketch and set operation creation methods and the public static methods into one place.

Author:

Lee Rhodes

Method Summary

Modifier and Type	Method and Description
static double	getEstimate(Memory srcMem) Gets the unique count estimate from a valid memory image of a Sketch
static double	getLowerBound(int numStdDev, Memory srcMem) Gets the approximate lower error bound from a valid memory image of a Sketch given the specified number of Standard Deviations.
static int	getMaxCompactSketchBytes(int numberOfEntries) Ref: Sketch.getMaxCompactSketchBytes(int)
static int	getMaxIntersectionBytes(int nomEntries) Ref: SetOperation.getMaxIntersectionBytes(int)
static int	getMaxUnionBytes(int nomEntries) Ref: SetOperation.getMaxUnionBytes(int)
static int	getMaxUpdateSketchBytes(int nomEntries) Ref: Sketch.getMaxUpdateSketchBytes(int)
static int	getSerializationVersion(Memory srcMem) Ref: Sketch.getSerializationVersion(Memory)
static double	getUpperBound(int numStdDev, Memory srcMem) Gets the approximate upper error bound from a valid memory image of a Sketch given the specified number of Standard Deviations.
static SetOperation	heapifySetOperation(Memory srcMem) Ref: SetOperation.heapify(Memory)
static SetOperation	heapifySetOperation(Memory srcMem, long seed) Ref: SetOperation.heapify(Memory, long)
static Sketch	heapifySketch(Memory srcMem) Ref: Sketch.heapify(Memory)
static Sketch	heapifySketch(Memory srcMem, long seed) Ref: Sketch.heapify(Memory, long)
static SetOperationBuilder	setOperationBuilder() Ref: SetOperationBuilder
static UpdateSketchBuilder	updateSketchBuilder() Ref: UpdateSketchBuilder
static Intersection	wrapIntersection(Memory srcMem) Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Intersection
static SetOperation	wrapSetOperation(Memory srcMem) Ref: SetOperation.wrap(Memory)
static SetOperation	wrapSetOperation(Memory srcMem, long seed) Ref: SetOperation.wrap(Memory, long)
static Sketch	wrapSketch(Memory srcMem) Ref: Sketch.heapify(Memory)
static Sketch	wrapSketch(Memory srcMem, long seed) Ref: Sketch.wrap(Memory, long)
static Union	wrapUnion(Memory srcMem) Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Union

Methods inherited from class java.lang.Object

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

Method Detail

updateSketchBuilder

public static UpdateSketchBuilder updateSketchBuilder()

Ref: UpdateSketchBuilder

Returns:

UpdateSketchBuilder

heapifySketch

public static Sketch heapifySketch(Memory srcMem)

Ref: Sketch.heapify(Memory)

Parameters:

srcMem - Ref: Sketch.heapify(Memory) srcMem

Returns:

Sketch

heapifySketch

public static Sketch heapifySketch(Memory srcMem,
                                   long seed)

Ref: Sketch.heapify(Memory, long)

Parameters:

srcMem - Ref: Sketch.heapify(Memory, long) srcMem

seed - Ref: Sketch.heapify(Memory, long) seed

Returns:

Sketch

wrapSketch

public static Sketch wrapSketch(Memory srcMem)

Ref: Sketch.heapify(Memory)

Parameters:

srcMem - Ref: Sketch.heapify(Memory) srcMem

Returns:

Sketch

wrapSketch

public static Sketch wrapSketch(Memory srcMem,
                                long seed)

Ref: Sketch.wrap(Memory, long)

Parameters:

srcMem - Ref: Sketch.wrap(Memory, long) srcMem

seed - Ref: Sketch.wrap(Memory, long) seed

Returns:

Sketch

setOperationBuilder

public static SetOperationBuilder setOperationBuilder()

Ref: SetOperationBuilder

Returns:

SetOperationBuilder

heapifySetOperation

public static SetOperation heapifySetOperation(Memory srcMem)

Ref: SetOperation.heapify(Memory)

Parameters:

srcMem - Ref: SetOperation.heapify(Memory) srcMem

Returns:

SetOperation

heapifySetOperation

public static SetOperation heapifySetOperation(Memory srcMem,
                                               long seed)

Ref: SetOperation.heapify(Memory, long)

Parameters:

srcMem - Ref: SetOperation.heapify(Memory, long) srcMem

seed - Ref: SetOperation.heapify(Memory, long) seed

Returns:

SetOperation

wrapSetOperation

public static SetOperation wrapSetOperation(Memory srcMem)

Ref: SetOperation.wrap(Memory)

Parameters:

srcMem - Ref: SetOperation.wrap(Memory) srcMem

Returns:

SetOperation

wrapUnion

public static Union wrapUnion(Memory srcMem)

Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Union

Parameters:

srcMem - Ref: SetOperation.wrap(Memory) srcMem

Returns:

a Union backed by the given Memory

wrapIntersection

public static Intersection wrapIntersection(Memory srcMem)

Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Intersection

Parameters:

srcMem - Ref: SetOperation.wrap(Memory) srcMem

Returns:

a Intersection backed by the given Memory

wrapSetOperation

public static SetOperation wrapSetOperation(Memory srcMem,
                                            long seed)

Ref: SetOperation.wrap(Memory, long)

Parameters:

srcMem - Ref: SetOperation.wrap(Memory, long) srcMem

seed - Ref: SetOperation.wrap(Memory, long) seed

Returns:

SetOperation

getMaxCompactSketchBytes

public static int getMaxCompactSketchBytes(int numberOfEntries)

Ref: Sketch.getMaxCompactSketchBytes(int)

Parameters:

numberOfEntries - Ref: Sketch.getMaxCompactSketchBytes(int) numberOfEntries

Returns:

Ref: Sketch.getMaxCompactSketchBytes(int)

getMaxUpdateSketchBytes

public static int getMaxUpdateSketchBytes(int nomEntries)

Ref: Sketch.getMaxUpdateSketchBytes(int)

Parameters:

nomEntries - Ref: Sketch.getMaxUpdateSketchBytes(int) nomEntries

Returns:

Ref: Sketch.getMaxUpdateSketchBytes(int)

getSerializationVersion

public static int getSerializationVersion(Memory srcMem)

Ref: Sketch.getSerializationVersion(Memory)

Parameters:

srcMem - Ref: Sketch.getSerializationVersion(Memory) srcMem

Returns:

Ref: Sketch.getSerializationVersion(Memory)

getMaxUnionBytes

public static int getMaxUnionBytes(int nomEntries)

Ref: SetOperation.getMaxUnionBytes(int)

Parameters:

nomEntries - Ref: SetOperation.getMaxUnionBytes(int) nomEntries

Returns:

Ref: SetOperation.getMaxUnionBytes(int)

getMaxIntersectionBytes

public static int getMaxIntersectionBytes(int nomEntries)

Ref: SetOperation.getMaxIntersectionBytes(int)

Parameters:

nomEntries - Ref: SetOperation.getMaxIntersectionBytes(int) nomEntries

Returns:

Ref: SetOperation.getMaxIntersectionBytes(int)

getEstimate

public static double getEstimate(Memory srcMem)

Gets the unique count estimate from a valid memory image of a Sketch

Parameters:

srcMem - See Memory

Returns:

the sketch's best estimate of the cardinality of the input stream.

getUpperBound

public static double getUpperBound(int numStdDev,
                                   Memory srcMem)

Gets the approximate upper error bound from a valid memory image of a Sketch given the specified number of Standard Deviations. This will return getEstimate() if isEmpty() is true.

Parameters:

numStdDev - See Number of Standard Deviations

srcMem - See Memory

Returns:

the upper bound.

getLowerBound

public static double getLowerBound(int numStdDev,
                                   Memory srcMem)

Gets the approximate lower error bound from a valid memory image of a Sketch given the specified number of Standard Deviations. This will return getEstimate() if isEmpty() is true.

Parameters:

numStdDev - See Number of Standard Deviations

srcMem - See Memory

Returns:

the lower bound.