com.sun.labs.minion.retrieval
Class CollectionStats

java.lang.Object
  com.sun.labs.minion.retrieval.CollectionStats

public class CollectionStats
extends java.lang.Object

A container for collection level statistics that are coelesced out of the statistics associated with a number of partitons.

Field Summary

float	avgDocLen The average document length in the collection, in words.
protected DictionaryIterator	di
int	maxfdt The maximum term frequency in the collection.
int	maxft The maximum document frequency in the collection.
int	nd The number of distinct terms in the collection.
protected int	nDocs The total number of documents in the collection.
protected long	nTokens The number of tokens in the collection.
protected PartitionManager	pm A partition manager that will allow us to fetch collection-wide term statistics.
protected java.util.Map<java.lang.String,TermStatsImpl>	termStats A local cache of term stats.

Constructor Summary

CollectionStats(PartitionManager pm)

Method Summary

float	getAvgerageDocumentLength()
int	getNDistinct()
int	getNDocs()
long	getNTokens()
TermStatsImpl	getTermStats(java.lang.String s) Gets the collection-wide statistics for a given term name.
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

pm

protected PartitionManager pm

A partition manager that will allow us to fetch collection-wide term statistics.

di

protected DictionaryIterator di

termStats

protected java.util.Map<java.lang.String,TermStatsImpl> termStats

A local cache of term stats.

nDocs

protected int nDocs

The total number of documents in the collection.

nTokens

protected long nTokens

The number of tokens in the collection.

maxfdt

public int maxfdt

The maximum term frequency in the collection. For all terms t in the collection and all documents d in the partition, this is the maximum value of f_d,t, the frequency of term t in document d.

maxft

public int maxft

The maximum document frequency in the collection. This is given by the term that has the largest number of documents associated with it, across all dictionaries in the collection. This will most likely be an underestimate, as it most likely will not take into account the fact that the same term occurs in more than one partition!

nd

public int nd

The number of distinct terms in the collection. This is very likely an overestimate, as many terms will be shared in the various partitions' main dictionaries.

avgDocLen

public float avgDocLen

The average document length in the collection, in words.

Constructor Detail

CollectionStats

public CollectionStats(PartitionManager pm)

Method Detail

getTermStats

public TermStatsImpl getTermStats(java.lang.String s)

Gets the collection-wide statistics for a given term name.

getNDocs

public int getNDocs()

getNTokens

public long getNTokens()

getAvgerageDocumentLength

public float getAvgerageDocumentLength()

getNDistinct

public int getNDistinct()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object