Package org.apache.datasketches.theta

Class Sketches

java.lang.Object

org.apache.datasketches.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	Description
static int	getCompactSketchMaxBytes(int lgNomEntries)	Returns the maximum number of storage bytes required for a CompactSketch given the configured log_base2 of the number of nominal entries, which is a power of 2.
static double	getEstimate(org.apache.datasketches.memory.Memory srcMem)	Gets the unique count estimate from a valid memory image of a Sketch
static double	getLowerBound(int numStdDev, org.apache.datasketches.memory.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	getMaxAnotBResultBytes(int maxNomEntries)	Ref: SetOperation.getMaxAnotBResultBytes(int).
static int	getMaxCompactSketchBytes(int numberOfEntries)	Returns the maximum number of storage bytes required for a CompactSketch with the given number of actual entries.
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(org.apache.datasketches.memory.Memory srcMem)	Ref: Sketch.getSerializationVersion(Memory)
static double	getUpperBound(int numStdDev, org.apache.datasketches.memory.Memory srcMem)	Gets the approximate upper error bound from a valid memory image of a Sketch given the specified number of Standard Deviations.
static CompactSketch	heapifyCompactSketch(org.apache.datasketches.memory.Memory srcMem)	Ref: CompactSketch.heapify(Memory)
static CompactSketch	heapifyCompactSketch(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: CompactSketch.heapify(Memory, long)
static SetOperation	heapifySetOperation(org.apache.datasketches.memory.Memory srcMem)	Ref: SetOperation.heapify(Memory)
static SetOperation	heapifySetOperation(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: SetOperation.heapify(Memory, long)
static Sketch	heapifySketch(org.apache.datasketches.memory.Memory srcMem)	Ref: Sketch.heapify(Memory)
static Sketch	heapifySketch(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: Sketch.heapify(Memory, long)
static UpdateSketch	heapifyUpdateSketch(org.apache.datasketches.memory.Memory srcMem)	Ref: UpdateSketch.heapify(Memory)
static UpdateSketch	heapifyUpdateSketch(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: UpdateSketch.heapify(Memory, long)
static SetOperationBuilder	setOperationBuilder()	Ref: SetOperationBuilder
static UpdateSketchBuilder	updateSketchBuilder()	Ref: UpdateSketchBuilder
static CompactSketch	wrapCompactSketch(org.apache.datasketches.memory.Memory srcMem)	Ref: CompactSketch.wrap(Memory)
static CompactSketch	wrapCompactSketch(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: CompactSketch.wrap(Memory, long)
static Intersection	wrapIntersection(org.apache.datasketches.memory.Memory srcMem)	Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Intersection
static Intersection	wrapIntersection(org.apache.datasketches.memory.WritableMemory srcMem)	Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Intersection
static SetOperation	wrapSetOperation(org.apache.datasketches.memory.Memory srcMem)	Ref: SetOperation.wrap(Memory)
static SetOperation	wrapSetOperation(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: SetOperation.wrap(Memory, long)
static SetOperation	wrapSetOperation(org.apache.datasketches.memory.WritableMemory srcMem)	Ref: SetOperation.wrap(Memory)
static SetOperation	wrapSetOperation(org.apache.datasketches.memory.WritableMemory srcMem, long expectedSeed)	Ref: SetOperation.wrap(Memory, long)
static Sketch	wrapSketch(org.apache.datasketches.memory.Memory srcMem)	Ref: Sketch.wrap(Memory)
static Sketch	wrapSketch(org.apache.datasketches.memory.Memory srcMem, long expectedSeed)	Ref: Sketch.wrap(Memory, long)
static Union	wrapUnion(org.apache.datasketches.memory.Memory srcMem)	Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Union
static Union	wrapUnion(org.apache.datasketches.memory.WritableMemory srcMem)	Convenience method, calls SetOperation.wrap(Memory) and casts the result to a Union
static UpdateSketch	wrapUpdateSketch(org.apache.datasketches.memory.WritableMemory srcMem)	Ref: UpdateSketch.wrap(Memory)
static UpdateSketch	wrapUpdateSketch(org.apache.datasketches.memory.WritableMemory srcMem, long expectedSeed)	Ref: UpdateSketch.wrap(Memory, long)

Methods inherited from class java.lang.Object

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

Method Details

getEstimate

public static double getEstimate(org.apache.datasketches.memory.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.

getLowerBound

public static double getLowerBound(int numStdDev,
 org.apache.datasketches.memory.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.

getMaxAnotBResultBytes

public static int getMaxAnotBResultBytes(int maxNomEntries)

Ref: SetOperation.getMaxAnotBResultBytes(int). Returns the maximum number of bytes for the returned CompactSketch, given the maximum value of nomEntries of the first sketch A of AnotB.

Parameters:

maxNomEntries - the given value

Returns:

the maximum number of bytes.

getMaxCompactSketchBytes

public static int getMaxCompactSketchBytes(int numberOfEntries)

Returns the maximum number of storage bytes required for a CompactSketch with the given number of actual entries.

Parameters:

numberOfEntries - the actual number of retained entries stored in the sketch.

Returns:

the maximum number of storage bytes required for a CompactSketch with the given number of retained entries.

getCompactSketchMaxBytes

public static int getCompactSketchMaxBytes(int lgNomEntries)

Returns the maximum number of storage bytes required for a CompactSketch given the configured log_base2 of the number of nominal entries, which is a power of 2.

Parameters:

lgNomEntries - Nominal Entries

Returns:

the maximum number of storage bytes required for a CompactSketch with the given lgNomEntries.

See Also:

• Sketch.getCompactSketchMaxBytes(int)

getMaxIntersectionBytes

public static int getMaxIntersectionBytes(int nomEntries)

Ref: SetOperation.getMaxIntersectionBytes(int)

Parameters:

nomEntries - Ref: SetOperation.getMaxIntersectionBytes(int), nomEntries

Returns:

Ref: SetOperation.getMaxIntersectionBytes(int)

getMaxUnionBytes

public static int getMaxUnionBytes(int nomEntries)

Ref: SetOperation.getMaxUnionBytes(int)

Parameters:

nomEntries - Ref: SetOperation.getMaxUnionBytes(int), nomEntries

Returns:

Ref: SetOperation.getMaxUnionBytes(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(org.apache.datasketches.memory.Memory srcMem)

Ref: Sketch.getSerializationVersion(Memory)

Parameters:

srcMem - Ref: Sketch.getSerializationVersion(Memory), srcMem

Returns:

Ref: Sketch.getSerializationVersion(Memory)

getUpperBound

public static double getUpperBound(int numStdDev,
 org.apache.datasketches.memory.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.

heapifyCompactSketch

public static CompactSketch heapifyCompactSketch(org.apache.datasketches.memory.Memory srcMem)

Ref: CompactSketch.heapify(Memory)

Parameters:

srcMem - Ref: CompactSketch.heapify(Memory), srcMem

Returns:

CompactSketch

heapifyCompactSketch

public static CompactSketch heapifyCompactSketch(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: CompactSketch.heapify(Memory, long)

Parameters:

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

expectedSeed - Ref: CompactSketch.heapify(Memory, long), expectedSeed

Returns:

CompactSketch

wrapCompactSketch

public static CompactSketch wrapCompactSketch(org.apache.datasketches.memory.Memory srcMem)

Ref: CompactSketch.wrap(Memory)

Parameters:

srcMem - Ref: CompactSketch.wrap(Memory), srcMem

Returns:

CompactSketch

wrapCompactSketch

public static CompactSketch wrapCompactSketch(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: CompactSketch.wrap(Memory, long)

Parameters:

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

expectedSeed - Ref: CompactSketch.wrap(Memory, long), expectedSeed

Returns:

CompactSketch

heapifySetOperation

public static SetOperation heapifySetOperation(org.apache.datasketches.memory.Memory srcMem)

Ref: SetOperation.heapify(Memory)

Parameters:

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

Returns:

SetOperation

heapifySetOperation

public static SetOperation heapifySetOperation(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: SetOperation.heapify(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: SetOperation.heapify(Memory, long), expectedSeed

Returns:

SetOperation

heapifySketch

public static Sketch heapifySketch(org.apache.datasketches.memory.Memory srcMem)

Ref: Sketch.heapify(Memory)

Parameters:

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

Returns:

Sketch

heapifySketch

public static Sketch heapifySketch(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: Sketch.heapify(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: Sketch.heapify(Memory, long), expectedSeed

Returns:

Sketch

heapifyUpdateSketch

public static UpdateSketch heapifyUpdateSketch(org.apache.datasketches.memory.Memory srcMem)

Ref: UpdateSketch.heapify(Memory)

Parameters:

srcMem - Ref: UpdateSketch.heapify(Memory), srcMem

Returns:

UpdateSketch

heapifyUpdateSketch

public static UpdateSketch heapifyUpdateSketch(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: UpdateSketch.heapify(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: UpdateSketch.heapify(Memory, long), expectedSeed

Returns:

UpdateSketch

setOperationBuilder

public static SetOperationBuilder setOperationBuilder()

Ref: SetOperationBuilder

Returns:

SetOperationBuilder

updateSketchBuilder

public static UpdateSketchBuilder updateSketchBuilder()

Ref: UpdateSketchBuilder

Returns:

UpdateSketchBuilder

wrapIntersection

public static Intersection wrapIntersection(org.apache.datasketches.memory.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

wrapIntersection

public static Intersection wrapIntersection(org.apache.datasketches.memory.WritableMemory 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(org.apache.datasketches.memory.Memory srcMem)

Ref: SetOperation.wrap(Memory)

Parameters:

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

Returns:

SetOperation

wrapSetOperation

public static SetOperation wrapSetOperation(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: SetOperation.wrap(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: SetOperation.wrap(Memory, long), expectedSeed

Returns:

SetOperation

wrapSetOperation

public static SetOperation wrapSetOperation(org.apache.datasketches.memory.WritableMemory srcMem)

Ref: SetOperation.wrap(Memory)

Parameters:

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

Returns:

SetOperation

wrapSetOperation

public static SetOperation wrapSetOperation(org.apache.datasketches.memory.WritableMemory srcMem,
 long expectedSeed)

Ref: SetOperation.wrap(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: SetOperation.wrap(Memory, long), expectedSeed

Returns:

SetOperation

wrapSketch

public static Sketch wrapSketch(org.apache.datasketches.memory.Memory srcMem)

Ref: Sketch.wrap(Memory)

Parameters:

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

Returns:

Sketch

wrapSketch

public static Sketch wrapSketch(org.apache.datasketches.memory.Memory srcMem,
 long expectedSeed)

Ref: Sketch.wrap(Memory, long)

Parameters:

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

expectedSeed - the expectedSeed used to validate the given Memory image. Ref: Sketch.wrap(Memory, long), expectedSeed

Returns:

Sketch

wrapUnion

public static Union wrapUnion(org.apache.datasketches.memory.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

wrapUnion

public static Union wrapUnion(org.apache.datasketches.memory.WritableMemory 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

wrapUpdateSketch

public static UpdateSketch wrapUpdateSketch(org.apache.datasketches.memory.WritableMemory srcMem)

Ref: UpdateSketch.wrap(Memory)

Parameters:

srcMem - Ref: UpdateSketch.wrap(Memory), srcMem

Returns:

UpdateSketch

wrapUpdateSketch

public static UpdateSketch wrapUpdateSketch(org.apache.datasketches.memory.WritableMemory srcMem,
 long expectedSeed)

Ref: UpdateSketch.wrap(Memory, long)

Parameters:

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

expectedSeed - the seed used to validate the given Memory image. Ref: UpdateSketch.wrap(Memory, long), expectedSeed

Returns:

UpdateSketch