org.apache.datasketches.tuple.aninteger

Class IntegerSketch

java.lang.Object

org.apache.datasketches.tuple.Sketch<S>

org.apache.datasketches.tuple.UpdatableSketch<Integer,IntegerSummary>

org.apache.datasketches.tuple.aninteger.IntegerSketch

public class IntegerSketch
extends UpdatableSketch<Integer,IntegerSummary>

Author:

Lee Rhodes

Field Summary

Fields inherited from class org.apache.datasketches.tuple.Sketch

PREAMBLE_LONGS

Constructor Summary

Constructors

Constructor and Description
IntegerSketch(int lgK, IntegerSummary.Mode mode) Constructs this sketch with given lgK.
IntegerSketch(int lgK, int lgResizeFactor, float samplingProbability, IntegerSummary.Mode mode) Creates this sketch with the following parameters:
IntegerSketch(org.apache.datasketches.memory.Memory mem, IntegerSummary.Mode mode) Constructs this sketch from a Memory image, which must be from an IntegerSketch, and usually with data.

Method Summary

Modifier and Type	Method and Description
CompactSketch<S>	compact() Converts the current state of the sketch into a compact sketch
int	getCurrentCapacity() Get current capacity
int	getLgK() Get log_base2 of Nominal Entries
int	getNominalEntries() Get configured nominal number of entries
ResizeFactor	getResizeFactor() Get configured resize factor
int	getRetainedEntries()
float	getSamplingProbability() Get configured sampling probability
protected void	insertSummary(int index, S summary)
void	reset() Resets this sketch an empty state.
byte[]	toByteArray() This is to serialize an instance to a byte array.
void	trim() Rebuilds reducing the actual number of entries to the nominal number of entries if needed
void	update(long key, Integer value) Updates this sketch with a long key and U value.
void	update(String key, Integer value) Updates this sketch with a String key and U value.

Methods inherited from class org.apache.datasketches.tuple.UpdatableSketch

update, update, update, update

Methods inherited from class org.apache.datasketches.tuple.Sketch

getEstimate, getEstimate, getLowerBound, getLowerBound, getTheta, getThetaLong, getUpperBound, getUpperBound, isEmpty, isEstimationMode, iterator, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

IntegerSketch

public IntegerSketch(int lgK,
                     IntegerSummary.Mode mode)

Constructs this sketch with given lgK.

Parameters:

lgK - Log_base2 of Nominal Entries. See Nominal Entries

mode - The IntegerSummary mode to be used

IntegerSketch

public IntegerSketch(int lgK,
                     int lgResizeFactor,
                     float samplingProbability,
                     IntegerSummary.Mode mode)

Creates this sketch with the following parameters:

Parameters:

lgK - Log_base2 of Nominal Entries.

lgResizeFactor - log2(resizeFactor) - value from 0 to 3:

 0 - no resizing (max size allocated),
 1 - double internal hash table each time it reaches a threshold
 2 - grow four times
 3 - grow eight times (default)
 

samplingProbability - See Sampling Probability

mode - The IntegerSummary mode to be used

IntegerSketch

public IntegerSketch(org.apache.datasketches.memory.Memory mem,
                     IntegerSummary.Mode mode)

Constructs this sketch from a Memory image, which must be from an IntegerSketch, and usually with data.

Parameters:

mem - the given Memory

mode - The IntegerSummary mode to be used

Method Detail

update

public void update(String key,
                   Integer value)

Description copied from class: UpdatableSketch

Updates this sketch with a String key and U value. The value is passed to update() method of the Summary object associated with the key

Overrides:

update in class UpdatableSketch<Integer,IntegerSummary>

Parameters:

key - The given String key

value - The given U value

update

public void update(long key,
                   Integer value)

Description copied from class: UpdatableSketch

Updates this sketch with a long key and U value. The value is passed to update() method of the Summary object associated with the key

Overrides:

update in class UpdatableSketch<Integer,IntegerSummary>

Parameters:

key - The given long key

value - The given U value

getRetainedEntries

public int getRetainedEntries()

Specified by:

getRetainedEntries in class Sketch<S extends Summary>

Returns:

number of retained entries

getNominalEntries

public int getNominalEntries()

Get configured nominal number of entries

Returns:

nominal number of entries

getLgK

public int getLgK()

Get log_base2 of Nominal Entries

Returns:

log_base2 of Nominal Entries

getSamplingProbability

public float getSamplingProbability()

Get configured sampling probability

Returns:

sampling probability

getCurrentCapacity

public int getCurrentCapacity()

Get current capacity

Returns:

current capacity

getResizeFactor

public ResizeFactor getResizeFactor()

Get configured resize factor

Returns:

resize factor

trim

public void trim()

Rebuilds reducing the actual number of entries to the nominal number of entries if needed

reset

public void reset()

Resets this sketch an empty state.

compact

public CompactSketch<S> compact()

Converts the current state of the sketch into a compact sketch

Returns:

compact sketch

toByteArray

public byte[] toByteArray()

Description copied from class: Sketch

This is to serialize an instance to a byte array.

Specified by:

toByteArray in class Sketch<S extends Summary>

Returns:

serialized representation of the sketch

insertSummary

protected void insertSummary(int index,
                             S summary)