Class BasicStats

Stores all statistics commonly used ranking methods.

Note

This API is experimental and might change in incompatible ways in the next release.

Inheritance

object

Similarity.SimWeight

BasicStats

LMSimilarity.LMStats

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Lucene.Net.Search.Similarities

Assembly: Lucene.Net.dll

Syntax

public class BasicStats : Similarity.SimWeight

Constructors

BasicStats(string, float)

Constructor. Sets the query boost.

Declaration

public BasicStats(string field, float queryBoost)

Parameters

Type	Name	Description
string	field
float	queryBoost

Fields

m_avgFieldLength

The average field length.

Declaration

protected float m_avgFieldLength

Field Value

Type	Description
float

m_docFreq

The document frequency.

Declaration

protected long m_docFreq

Field Value

Type	Description
long

m_numberOfDocuments

The number of documents.

Declaration

protected long m_numberOfDocuments

Field Value

Type	Description
long

m_numberOfFieldTokens

The total number of tokens in the field.

Declaration

protected long m_numberOfFieldTokens

Field Value

Type	Description
long

m_queryBoost

Query's inner boost.

Declaration

protected readonly float m_queryBoost

Field Value

Type	Description
float

m_topLevelBoost

Any outer query's boost.

Declaration

protected float m_topLevelBoost

Field Value

Type	Description
float

m_totalBoost

For most Similarities, the immediate and the top level query boosts are not handled differently. Hence, this field is just the product of the other two.

Declaration

protected float m_totalBoost

Field Value

Type	Description
float

m_totalTermFreq

The total number of occurrences of this term across all documents.

Declaration

protected long m_totalTermFreq

Field Value

Type	Description
long

Properties

AvgFieldLength

Returns the average field length.

Declaration

public virtual float AvgFieldLength { get; set; }

Property Value

Type	Description
float

DocFreq

Returns the document frequency.

Declaration

public virtual long DocFreq { get; set; }

Property Value

Type	Description
long

Field

The field.

Declaration

public string Field { get; }

Property Value

Type	Description
string

NumberOfDocuments

Gets or Sets the number of documents.

Declaration

public virtual long NumberOfDocuments { get; set; }

Property Value

Type	Description
long

NumberOfFieldTokens

Returns the total number of tokens in the field.

Declaration

public virtual long NumberOfFieldTokens { get; set; }

Property Value

Type	Description
long

See Also

SumTotalTermFreq

TotalBoost

Returns the total boost.

Declaration

public virtual float TotalBoost { get; }

Property Value

Type	Description
float

TotalTermFreq

Returns the total number of occurrences of this term across all documents.

Declaration

public virtual long TotalTermFreq { get; set; }

Property Value

Type	Description
long

Methods

GetValueForNormalization()

The square of the raw normalization value.

Declaration

public override float GetValueForNormalization()

Returns

Type	Description
float

Overrides

Similarity.SimWeight.GetValueForNormalization()

See Also

RawNormalizationValue()

Normalize(float, float)

No normalization is done. topLevelBoost is saved in the object, however.

Declaration

public override void Normalize(float queryNorm, float topLevelBoost)

Parameters

Type	Name	Description
float	queryNorm
float	topLevelBoost

Overrides

Similarity.SimWeight.Normalize(float, float)

RawNormalizationValue()

Computes the raw normalization value. This basic implementation returns the query boost. Subclasses may override this method to include other factors (such as idf), or to save the value for inclusion in Normalize(float, float), etc.

Declaration

protected virtual float RawNormalizationValue()

Returns

Type	Description
float