net.obsearch.index.ghs
Class AbstractSketch64<O extends OB,B extends BucketObject<O>,Q,BC extends BucketContainer<O,B,Q>>

java.lang.Object
  net.obsearch.index.AbstractOBIndex<O>
      net.obsearch.index.pivot.AbstractPivotOBIndex<O>
          net.obsearch.index.bucket.AbstractBucketIndex<O,B,Q,BC>
              net.obsearch.index.sorter.AbstractBucketSorter<O,B,Q,BC,SketchProjection,CBitVector>
                  net.obsearch.index.ghs.AbstractSketch64<O,B,Q,BC>

All Implemented Interfaces:

Index<O>

Direct Known Subclasses:

Sketch64Byte, Sketch64Double, Sketch64Float, Sketch64Int, Sketch64Long, Sketch64Short

public abstract class AbstractSketch64<O extends OB,B extends BucketObject<O>,Q,BC extends BucketContainer<O,B,Q>>
extends AbstractBucketSorter<O,B,Q,BC,SketchProjection,CBitVector>

AbstractSketch64 encapsulates functionality common to a Sketch. The maximum number of bits has been artificially set to 64 bits to optimize performance. If you use less than 64 bits the keys used for the sketch only use the amount of bits the user specifies. Nevertheless the handling of priority queues and the matching itself occurs on longs. It should affect considerably AMD64 architectures. If you are using a 32 bits processor or operating system, then this implementation will not be as efficient.

Author:

Arnoldo Jose Muller Molina

Nested Class Summary

Nested classes/interfaces inherited from class net.obsearch.index.bucket.AbstractBucketIndex

AbstractBucketIndex.BucketIterator

Field Summary

protected int[][]	distortionStats Distortion stats
protected int	m Number of bits.
protected IncrementalPairPivotSelector<O>	maskPivotSelector Pivot selector for the masks.
protected O[][]	pivotGrid pivot grid.

Fields inherited from class net.obsearch.index.sorter.AbstractBucketSorter

bucketCache, bucketPivotCount, kEstimators, projections, projectionStorage, userK

Fields inherited from class net.obsearch.index.bucket.AbstractBucketIndex

Buckets

Fields inherited from class net.obsearch.index.pivot.AbstractPivotOBIndex

intrinsicDimensionalityPairs, pivots, pivotSelector

Fields inherited from class net.obsearch.index.AbstractOBIndex

A, fact, isFrozen, stats, type

Fields inherited from interface net.obsearch.Index

ID_SIZE

Constructor Summary

AbstractSketch64()

AbstractSketch64(Class<O> type, IncrementalPairPivotSelector<O> pivotSelector, int m, int bucketPivotCount)

Method Summary

protected CBitVector	bytesToCompactRepresentation(byte[] data)
protected byte[]	compactRepresentationToBytes(CBitVector cp)
void	debugDist()
void	freeze() Freezes the index.
protected void	updateDistance(SketchProjection query, CBitVector proj, FixedPriorityQueue<SketchProjection> queue) Calculates the distance between a query and some projection

Methods inherited from class net.obsearch.index.sorter.AbstractBucketSorter

bucketStats, calculateEstimators, close, estimateK, freezeDefault, getAddress, getAllObjects, getBucketContainer, getBucketPivotCount, getCPSize, getExpectedEP, getKQuery, getMaxK, getPInstance, getProjection, init, initByteArrayBuckets, initCache, insertBucket, insertBucketBulk, loadMasks, maxKEstimation, maxKEstimationAux, printEstimation, searchBuckets, setExpectedError, setKAlpha, setMaxK, setSampleSize

Methods inherited from class net.obsearch.index.bucket.AbstractBucketIndex

debug, deleteAux, exists, getBucket, getBuckets, getObjectFreeze, idMap, insertAux, insertAuxBulk, instantiateBucketContainer, iterateBuckets, primitiveDataTypeSize

Methods inherited from class net.obsearch.index.pivot.AbstractPivotOBIndex

calculateIntrinsicDimensionality, createPivotsArray, getObjects, getPivotCount, selectPivots

Methods inherited from class net.obsearch.index.AbstractOBIndex

assertFrozen, bytesToObject, bytesToObject, clearACache, databaseSize, delete, distance, emptyPivotsArray, findAux, getBox, getObject, getStats, getType, initStorageDevices, insert, insert, insertBulk, insertBulk, intrinsicDimensionality, isFrozen, isPreFreeze, isPreFreezeCheck, loadObject, loadPivots, objectToByteBuffer, objectToBytes, resetStats, serializePivots, setFixedRecord, setFixedRecord, setIdAutoGeneration, setPreFreeze, setPreFreezeCheck, totalBoxes

Methods inherited from class java.lang.Object

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

Field Detail

m

protected int m

Number of bits.

pivotGrid

protected O extends OB[][] pivotGrid

pivot grid.

distortionStats

protected int[][] distortionStats

Distortion stats

maskPivotSelector

protected IncrementalPairPivotSelector<O extends OB> maskPivotSelector

Pivot selector for the masks.

Constructor Detail

AbstractSketch64

public AbstractSketch64()

AbstractSketch64

public AbstractSketch64(Class<O> type,
                        IncrementalPairPivotSelector<O> pivotSelector,
                        int m,
                        int bucketPivotCount)
                 throws OBStorageException,
                        OBException

Throws:

OBStorageException

OBException

Method Detail

compactRepresentationToBytes

protected byte[] compactRepresentationToBytes(CBitVector cp)

Specified by:

compactRepresentationToBytes in class AbstractBucketSorter<O extends OB,B extends BucketObject<O>,Q,BC extends BucketContainer<O,B,Q>,SketchProjection,CBitVector>

bytesToCompactRepresentation

protected CBitVector bytesToCompactRepresentation(byte[] data)

Specified by:

bytesToCompactRepresentation in class AbstractBucketSorter<O extends OB,B extends BucketObject<O>,Q,BC extends BucketContainer<O,B,Q>,SketchProjection,CBitVector>

freeze

public void freeze()
            throws AlreadyFrozenException,
                   IllegalIdException,
                   OutOfRangeException,
                   IllegalAccessException,
                   InstantiationException,
                   OBException,
                   PivotsUnavailableException,
                   IOException

Description copied from interface: Index

Freezes the index. From this point data can be inserted, searched and deleted. The index might deteriorate at some point so every once in a while it is a good idea to rebuild the index. A PivotSelector must be executed before calling this method.

Specified by:

freeze in interface Index<O extends OB>

Overrides:

freeze in class AbstractPivotOBIndex<O extends OB>

Throws:

AlreadyFrozenException - If the index was already frozen and the user attempted to freeze it again

IllegalIdException - This exception is left as a Debug flag. If you receive this exception please report the problem to: http://code.google.com/p/obsearch/issues/list

OutOfRangeException - If the distance of any object to any other object exceeds the range defined by the user.

IllegalAccessException - If there is a problem when instantiating objects O

InstantiationException - If there is a problem when instantiating objects O

OBStorageException - If something goes wrong with the DB

OBException - User generated exception

PivotsUnavailableException

IOException - if the index serialization process fails

See Also:

Index.freeze()

debugDist

public void debugDist()
               throws IllegalIdException,
                      OBStorageException,
                      IllegalAccessException,
                      InstantiationException,
                      OBException,
                      IOException

Throws:

IllegalIdException

OBStorageException

IllegalAccessException

InstantiationException

OBException

IOException

updateDistance

protected void updateDistance(SketchProjection query,
                              CBitVector proj,
                              FixedPriorityQueue<SketchProjection> queue)

Description copied from class: AbstractBucketSorter

Calculates the distance between a query and some projection

Specified by:

updateDistance in class AbstractBucketSorter<O extends OB,B extends BucketObject<O>,Q,BC extends BucketContainer<O,B,Q>,SketchProjection,CBitVector>