Class Similarity.SimWeight

Stores the weight for a query across the indexed collection. this abstract implementation is empty; descendants of Similarity should subclass Similarity.SimWeight and define the statistics they require in the subclass. Examples include idf, average field length, etc.

Inheritance

System.Object

Similarity.SimWeight

BasicStats

Namespace: Lucene.Net.Search.Similarities

Assembly: Lucene.Net.dll

Syntax

public abstract class SimWeight : object

Constructors

SimWeight()

Sole constructor. (For invocation by subclass constructors, typically implicit.)

Declaration

public SimWeight()

Methods

GetValueForNormalization()

The value for normalization of contained query clauses (e.g. sum of squared weights).

NOTE: a Similarity implementation might not use any query normalization at all, its not required. However, if it wants to participate in query normalization, it can return a value here.

Declaration

public abstract float GetValueForNormalization()

Returns

Type	Description
System.Single

Normalize(Single, Single)

Assigns the query normalization factor and boost from parent queries to this.

NOTE: a Similarity implementation might not use this normalized value at all, its not required. However, its usually a good idea to at least incorporate the topLevelBoost (e.g. from an outer BooleanQuery) into its score.

Declaration

public abstract void Normalize(float queryNorm, float topLevelBoost)

Parameters

Type	Name	Description
System.Single	queryNorm
System.Single	topLevelBoost