com.sun.labs.minion.indexer.partition
Class CachedDocumentVectorLengths

java.lang.Object
  com.sun.labs.minion.indexer.partition.DocumentVectorLengths
      com.sun.labs.minion.indexer.partition.CachedDocumentVectorLengths

public class CachedDocumentVectorLengths
extends DocumentVectorLengths

Field Summary

Fields inherited from class com.sun.labs.minion.indexer.partition.DocumentVectorLengths

BUFF_SIZE, fieldLens, logTag, part, raf, vecLens, vlFile

Constructor Summary

CachedDocumentVectorLengths(DiskPartition part, boolean adjustStats)

Method Summary

float	getVectorLength(int docID) Gets the length of a document associated with this partition.
float	getVectorLength(int docID, int fieldID) Gets the length of a document associated with this partition.
void	normalize(int[] docs, float[] scores, int p, float qw, int fieldID) Normalizes a set of document scores all in one go.

Methods inherited from class com.sun.labs.minion.indexer.partition.DocumentVectorLengths

calculateLengths, close

Methods inherited from class java.lang.Object

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

Constructor Detail

CachedDocumentVectorLengths

public CachedDocumentVectorLengths(DiskPartition part,
                                   boolean adjustStats)
                            throws java.io.IOException

Throws:

java.io.IOException

Method Detail

getVectorLength

public float getVectorLength(int docID)

Description copied from class: DocumentVectorLengths

Gets the length of a document associated with this partition. This will be used at query and classification time. Note that our buffer uses 0 based indexing, so we need to subtract one from the document ID!

Overrides:

getVectorLength in class DocumentVectorLengths

Parameters:

docID - the ID of the document whose vector length we wish to retrieve.

Returns:

the vector length of the document with the given ID

getVectorLength

public float getVectorLength(int docID,
                             int fieldID)

Description copied from class: DocumentVectorLengths

Gets the length of a document associated with this partition. This will be used at query and classification time. Note that our buffer uses 0 based indexing, so we need to subtract one from the document ID!

Overrides:

getVectorLength in class DocumentVectorLengths

Parameters:

docID - the ID of the document whose vector length we wish to retrieve.

fieldID - the ID of the field for which we're looking for the length. A field ID of -1 is interpreted as a request for the length using all vectored fields. If this field was not vectored, then a length of 1 is returned, so that dividing weights by document lengths won't cause problems.

Returns:

the length of the vector for the given ID and vectored field

normalize

public void normalize(int[] docs,
                      float[] scores,
                      int p,
                      float qw,
                      int fieldID)

Normalizes a set of document scores all in one go.

Overrides:

normalize in class DocumentVectorLengths

Parameters:

docs - the document IDs to normalize

scores - the document scores

p - the number of document IDs and scores in the array

qw - the query weight to use for normalization

fieldID - the ID of the field that the scores were computed from and that should be used for normalization.