xapian-core  1.4.19
Classes | Public Types | Public Member Functions | Protected Types | Protected Member Functions | Private Member Functions | Private Attributes | List of all members
Xapian::Weight Class Referenceabstract

Abstract base class for weighting schemes. More...

#include <weight.h>

+ Inheritance diagram for Xapian::Weight:

Classes

class  Internal
 Class to hold statistics for a given collection. More...
 

Public Types

enum  type_smoothing {
  TWO_STAGE_SMOOTHING = 1, DIRICHLET_SMOOTHING = 2, ABSOLUTE_DISCOUNT_SMOOTHING = 3, JELINEK_MERCER_SMOOTHING = 4,
  DIRICHLET_PLUS_SMOOTHING = 5
}
 Type of smoothing to use with the Language Model Weighting scheme. More...
 

Public Member Functions

 Weight ()
 Default constructor, needed by subclass constructors. More...
 
virtual ~Weight ()
 Virtual destructor, because we have virtual methods. More...
 
virtual Weightclone () const =0
 Clone this object. More...
 
virtual std::string name () const
 Return the name of this weighting scheme. More...
 
virtual std::string serialise () const
 Return this object's parameters serialised as a single string. More...
 
virtual Weightunserialise (const std::string &serialised) const
 Unserialise parameters. More...
 
virtual double get_sumpart (Xapian::termcount wdf, Xapian::termcount doclen, Xapian::termcount uniqterms) const =0
 Calculate the weight contribution for this object's term to a document. More...
 
virtual double get_maxpart () const =0
 Return an upper bound on what get_sumpart() can return for any document. More...
 
virtual double get_sumextra (Xapian::termcount doclen, Xapian::termcount uniqterms) const =0
 Calculate the term-independent weight component for a document. More...
 
virtual double get_maxextra () const =0
 Return an upper bound on what get_sumextra() can return for any document. More...
 

Protected Types

enum  stat_flags {
  COLLECTION_SIZE = 1, RSET_SIZE = 2, AVERAGE_LENGTH = 4, TERMFREQ = 8,
  RELTERMFREQ = 16, QUERY_LENGTH = 32, WQF = 64, WDF = 128,
  DOC_LENGTH = 256, DOC_LENGTH_MIN = 512, DOC_LENGTH_MAX = 1024, WDF_MAX = 2048,
  COLLECTION_FREQ = 4096, UNIQUE_TERMS = 8192, TOTAL_LENGTH = COLLECTION_SIZE | AVERAGE_LENGTH
}
 Stats which the weighting scheme can use (see need_stat()). More...
 

Protected Member Functions

void need_stat (stat_flags flag)
 Tell Xapian that your subclass will want a particular statistic. More...
 
virtual void init (double factor)=0
 Allow the subclass to perform any initialisation it needs to. More...
 
 Weight (const Weight &)
 Don't allow copying. More...
 
Xapian::doccount get_collection_size () const
 The number of documents in the collection. More...
 
Xapian::doccount get_rset_size () const
 The number of documents marked as relevant. More...
 
Xapian::doclength get_average_length () const
 The average length of a document in the collection. More...
 
Xapian::doccount get_termfreq () const
 The number of documents which this term indexes. More...
 
Xapian::doccount get_reltermfreq () const
 The number of relevant documents which this term indexes. More...
 
Xapian::termcount get_collection_freq () const
 The collection frequency of the term. More...
 
Xapian::termcount get_query_length () const
 The length of the query. More...
 
Xapian::termcount get_wqf () const
 The within-query-frequency of this term. More...
 
Xapian::termcount get_doclength_upper_bound () const
 An upper bound on the maximum length of any document in the database. More...
 
Xapian::termcount get_doclength_lower_bound () const
 A lower bound on the minimum length of any document in the database. More...
 
Xapian::termcount get_wdf_upper_bound () const
 An upper bound on the wdf of this term. More...
 
Xapian::totallength get_total_length () const
 Total length of all documents in the collection. More...
 

Private Member Functions

void operator= (const Weight &)
 Don't allow assignment. More...
 
void init_ (const Internal &stats, Xapian::termcount query_len_, const std::string &term, Xapian::termcount wqf_, double factor)
 
void init_ (const Internal &stats, Xapian::termcount query_len_, const std::string &term, Xapian::termcount wqf_, double factor, void *postlist)
 
void init_ (const Internal &stats, Xapian::termcount query_len_, double factor, Xapian::doccount termfreq, Xapian::doccount reltermfreq, Xapian::termcount collection_freq)
 
void init_ (const Internal &stats, Xapian::termcount query_len_)
 
bool get_sumpart_needs_doclength_ () const
 
bool get_sumpart_needs_wdf_ () const
 
bool get_sumpart_needs_uniqueterms_ () const
 
bool is_bool_weight_ () const
 

Private Attributes

stat_flags stats_needed
 A bitmask of the statistics this weighting scheme needs. More...
 
Xapian::doccount collection_size_
 The number of documents in the collection. More...
 
Xapian::doccount rset_size_
 The number of documents marked as relevant. More...
 
Xapian::doclength average_length_
 The average length of a document in the collection. More...
 
Xapian::doccount termfreq_
 The number of documents which this term indexes. More...
 
Xapian::termcount collectionfreq_
 
Xapian::doccount reltermfreq_
 The number of relevant documents which this term indexes. More...
 
Xapian::termcount query_length_
 The length of the query. More...
 
Xapian::termcount wqf_
 The within-query-frequency of this term. More...
 
Xapian::termcount doclength_lower_bound_
 A lower bound on the minimum length of any document in the database. More...
 
Xapian::termcount doclength_upper_bound_
 An upper bound on the maximum length of any document in the database. More...
 
Xapian::termcount wdf_upper_bound_
 An upper bound on the wdf of this term. More...
 

Detailed Description

Abstract base class for weighting schemes.

Definition at line 35 of file weight.h.

Member Enumeration Documentation

◆ stat_flags

Stats which the weighting scheme can use (see need_stat()).

Enumerator
COLLECTION_SIZE 

Number of documents in the collection.

RSET_SIZE 

Number of documents in the RSet.

AVERAGE_LENGTH 

Average length of documents in the collection.

TERMFREQ 

How many documents the current term is in.

RELTERMFREQ 

How many documents in the RSet the current term is in.

QUERY_LENGTH 

Sum of wqf for terms in the query.

WQF 

Within-query-frequency of the current term.

WDF 

Within-document-frequency of the current term in the current document.

DOC_LENGTH 

Length of the current document (sum wdf).

DOC_LENGTH_MIN 

Lower bound on (non-zero) document lengths.

DOC_LENGTH_MAX 

Upper bound on document lengths.

WDF_MAX 

Upper bound on wdf.

COLLECTION_FREQ 

Sum of wdf over the whole collection for the current term.

UNIQUE_TERMS 

Number of unique terms in the current document.

TOTAL_LENGTH 

Sum of lengths of all documents in the collection.

This gives the total number of term occurrences.

Definition at line 38 of file weight.h.

◆ type_smoothing

Type of smoothing to use with the Language Model Weighting scheme.

Default is TWO_STAGE_SMOOTHING.

Enumerator
TWO_STAGE_SMOOTHING 
DIRICHLET_SMOOTHING 
ABSOLUTE_DISCOUNT_SMOOTHING 
JELINEK_MERCER_SMOOTHING 
DIRICHLET_PLUS_SMOOTHING 

Definition at line 147 of file weight.h.

Constructor & Destructor Documentation

◆ Weight() [1/2]

Xapian::Weight::Weight ( )
inline

Default constructor, needed by subclass constructors.

Definition at line 141 of file weight.h.

◆ ~Weight()

Xapian::Weight::~Weight ( )
virtual

Virtual destructor, because we have virtual methods.

Definition at line 132 of file weight.cc.

◆ Weight() [2/2]

Xapian::Weight::Weight ( const Weight )
protected

Don't allow copying.

This would ideally be private, but that causes a compilation error with GCC 4.1 (which appears to be a bug).

Member Function Documentation

◆ clone()

virtual Weight* Xapian::Weight::clone ( ) const
pure virtual

Clone this object.

This method allocates and returns a copy of the object it is called on.

If your subclass is called FooWeight and has parameters a and b, then you would implement FooWeight::clone() like so:

FooWeight * FooWeight::clone() const { return new FooWeight(a, b); }

Note that the returned object will be deallocated by Xapian after use with "delete". If you want to handle the deletion in a special way (for example when wrapping the Xapian API for use from another language) then you can define a static operator delete method in your subclass as shown here: https://trac.xapian.org/ticket/554#comment:1

Implemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, CheckStatsWeight, Xapian::IfB2Weight, CheckInitWeight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, ZWeight, and LazyWeight.

Referenced by Xapian::Enquire::set_weighting_scheme().

◆ get_average_length()

Xapian::doclength Xapian::Weight::get_average_length ( ) const
inlineprotected

The average length of a document in the collection.

Definition at line 369 of file weight.h.

Referenced by Xapian::InL2Weight::init(), Xapian::IfB2Weight::init(), Xapian::IneB2Weight::init(), Xapian::BB2Weight::init(), Xapian::PL2Weight::init(), and Xapian::PL2PlusWeight::init().

◆ get_collection_freq()

Xapian::termcount Xapian::Weight::get_collection_freq ( ) const
inlineprotected

◆ get_collection_size()

Xapian::doccount Xapian::Weight::get_collection_size ( ) const
inlineprotected

◆ get_doclength_lower_bound()

Xapian::termcount Xapian::Weight::get_doclength_lower_bound ( ) const
inlineprotected

A lower bound on the minimum length of any document in the database.

This bound does not include any zero-length documents.

This should only be used by get_maxpart() and get_maxextra().

Definition at line 400 of file weight.h.

Referenced by Xapian::TfIdfWeight::get_maxpart(), Xapian::InL2Weight::init(), Xapian::IfB2Weight::init(), Xapian::IneB2Weight::init(), Xapian::BB2Weight::init(), Xapian::PL2Weight::init(), and Xapian::PL2PlusWeight::init().

◆ get_doclength_upper_bound()

Xapian::termcount Xapian::Weight::get_doclength_upper_bound ( ) const
inlineprotected

An upper bound on the maximum length of any document in the database.

This should only be used by get_maxpart() and get_maxextra().

Definition at line 390 of file weight.h.

Referenced by Xapian::BB2Weight::init(), Xapian::PL2Weight::init(), and Xapian::PL2PlusWeight::init().

◆ get_maxextra()

virtual double Xapian::Weight::get_maxextra ( ) const
pure virtual

Return an upper bound on what get_sumextra() can return for any document.

This information is used by the matcher to perform various optimisations, so strive to make the bound as tight as possible.

Implemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, CheckStatsWeight, Xapian::IneB2Weight, Xapian::IfB2Weight, CheckInitWeight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, ZWeight, and LazyWeight.

◆ get_maxpart()

virtual double Xapian::Weight::get_maxpart ( ) const
pure virtual

◆ get_query_length()

Xapian::termcount Xapian::Weight::get_query_length ( ) const
inlineprotected

The length of the query.

Definition at line 381 of file weight.h.

◆ get_reltermfreq()

Xapian::doccount Xapian::Weight::get_reltermfreq ( ) const
inlineprotected

The number of relevant documents which this term indexes.

Definition at line 375 of file weight.h.

◆ get_rset_size()

Xapian::doccount Xapian::Weight::get_rset_size ( ) const
inlineprotected

The number of documents marked as relevant.

Definition at line 366 of file weight.h.

◆ get_sumextra()

virtual double Xapian::Weight::get_sumextra ( Xapian::termcount  doclen,
Xapian::termcount  uniqterms 
) const
pure virtual

Calculate the term-independent weight component for a document.

The parameter gives information about the document which may be used in the calculations:

Parameters
doclenThe document's length (unnormalised).
uniqtermsThe number of unique terms in the document.

Implemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, CheckStatsWeight, Xapian::IneB2Weight, Xapian::IfB2Weight, CheckInitWeight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, ZWeight, and LazyWeight.

Referenced by ExtraWeightPostList::get_weight().

◆ get_sumpart()

virtual double Xapian::Weight::get_sumpart ( Xapian::termcount  wdf,
Xapian::termcount  doclen,
Xapian::termcount  uniqterms 
) const
pure virtual

Calculate the weight contribution for this object's term to a document.

The parameters give information about the document which may be used in the calculations:

Parameters
wdfThe within document frequency of the term in the document.
doclenThe document's length (unnormalised).
uniqtermsNumber of unique terms in the document (used for absolute smoothing).

Implemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, CheckStatsWeight, Xapian::IfB2Weight, CheckInitWeight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, ZWeight, and LazyWeight.

◆ get_sumpart_needs_doclength_()

bool Xapian::Weight::get_sumpart_needs_doclength_ ( ) const
inlineprivate

Return true if the document length is needed.

If this method returns true, then the document length will be fetched and passed to get_sumpart(). Otherwise 0 may be passed for the document length.

Definition at line 322 of file weight.h.

Referenced by LeafPostList::resolve_lazy_termweight().

◆ get_sumpart_needs_uniqueterms_()

bool Xapian::Weight::get_sumpart_needs_uniqueterms_ ( ) const
inlineprivate

Return true if the number of unique terms is needed.

If this method returns true, then the number of unique terms will be fetched and passed to get_sumpart(). Otherwise 0 may be passed for the number of unique terms.

Definition at line 341 of file weight.h.

◆ get_sumpart_needs_wdf_()

bool Xapian::Weight::get_sumpart_needs_wdf_ ( ) const
inlineprivate

Return true if the WDF is needed.

If this method returns true, then the WDF will be fetched and passed to get_sumpart(). Otherwise 0 may be passed for the wdf.

Definition at line 331 of file weight.h.

◆ get_termfreq()

Xapian::doccount Xapian::Weight::get_termfreq ( ) const
inlineprotected

◆ get_total_length()

Xapian::totallength Xapian::Weight::get_total_length ( ) const
inlineprotected

Total length of all documents in the collection.

Definition at line 413 of file weight.h.

◆ get_wdf_upper_bound()

Xapian::termcount Xapian::Weight::get_wdf_upper_bound ( ) const
inlineprotected

◆ get_wqf()

Xapian::termcount Xapian::Weight::get_wqf ( ) const
inlineprotected

◆ init()

virtual void Xapian::Weight::init ( double  factor)
protectedpure virtual

Allow the subclass to perform any initialisation it needs to.

Parameters
factorAny scaling factor (e.g. from OP_SCALE_WEIGHT). If the Weight object is for the term-independent weight supplied by get_sumextra()/get_maxextra(), then init(0.0) is called (starting from Xapian 1.2.11 and 1.3.1 - earlier versions failed to call init() for such Weight objects).

Implemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, CheckStatsWeight, Xapian::IfB2Weight, CheckInitWeight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, ZWeight, and LazyWeight.

◆ init_() [1/4]

void Xapian::Weight::init_ ( const Internal stats,
Xapian::termcount  query_len_,
const std::string &  term,
Xapian::termcount  wqf_,
double  factor 
)
private

Initialise this object to calculate weights for term term.

Old version of method, as used by 1.4.18 and earlier. This should only be referenced from inside the library and 1.4.19 and later will call the new version instead. We continue to provide it mainly to avoid triggering ABI checking tools.

Parameters
statsSource of statistics.
query_len_Query length.
termThe term for the new object.
wqf_The within-query-frequency of term.
factorAny scaling factor (e.g. from OP_SCALE_WEIGHT).

Definition at line 93 of file weight.cc.

Referenced by LocalSubMatch::open_post_list(), and LeafPostList::resolve_lazy_termweight().

◆ init_() [2/4]

void Xapian::Weight::init_ ( const Internal stats,
Xapian::termcount  query_len_,
const std::string &  term,
Xapian::termcount  wqf_,
double  factor,
void *  postlist 
)
private

Initialise this object to calculate weights for term term.

Parameters
statsSource of statistics.
query_len_Query length.
termThe term for the new object.
wqf_The within-query-frequency of term.
factorAny scaling factor (e.g. from OP_SCALE_WEIGHT).
postlistPointer to a LeafPostList for the term (cast to void* to avoid needing to forward declare class LeafPostList in public API headers) which can be used to get wdf upper bound

Definition at line 60 of file weight.cc.

References Assert, Xapian::Weight::Internal::collection_size, Xapian::Weight::Internal::db, Xapian::Weight::Internal::get_average_length(), Xapian::Database::get_doclength_lower_bound(), Xapian::Database::get_doclength_upper_bound(), Xapian::Weight::Internal::get_stats(), LeafPostList::get_wdf_upper_bound(), Xapian::Database::get_wdf_upper_bound(), LOGCALL_VOID, Xapian::Weight::Internal::rset_size, and usual.

◆ init_() [3/4]

void Xapian::Weight::init_ ( const Internal stats,
Xapian::termcount  query_len_,
double  factor,
Xapian::doccount  termfreq,
Xapian::doccount  reltermfreq,
Xapian::termcount  collection_freq 
)
private

Initialise this object to calculate weights for a synonym.

Parameters
statsSource of statistics.
query_len_Query length.
factorAny scaling factor (e.g. from OP_SCALE_WEIGHT).
termfreqThe termfreq to use.
reltermfreqThe reltermfreq to use.
collection_freqThe collection frequency to use.

Definition at line 100 of file weight.cc.

References Xapian::Weight::Internal::collection_size, Xapian::Weight::Internal::db, Xapian::Weight::Internal::get_average_length(), Xapian::Database::get_doclength_lower_bound(), Xapian::Database::get_doclength_upper_bound(), LOGCALL_VOID, and Xapian::Weight::Internal::rset_size.

◆ init_() [4/4]

void Xapian::Weight::init_ ( const Internal stats,
Xapian::termcount  query_len_ 
)
private

Initialise this object to calculate the extra weight component.

Parameters
statsSource of statistics.
query_len_Query length.

Definition at line 39 of file weight.cc.

References Xapian::Weight::Internal::collection_size, Xapian::Weight::Internal::db, Xapian::Weight::Internal::get_average_length(), Xapian::Database::get_doclength_lower_bound(), Xapian::Database::get_doclength_upper_bound(), LOGCALL_VOID, and Xapian::Weight::Internal::rset_size.

◆ is_bool_weight_()

bool Xapian::Weight::is_bool_weight_ ( ) const
inlineprivate

Test if this is a BoolWeight object.

Definition at line 346 of file weight.h.

References name.

◆ name()

string Xapian::Weight::name ( ) const
virtual

Return the name of this weighting scheme.

This name is used by the remote backend. It is passed along with the serialised parameters to the remote server so that it knows which class to create.

Return the full namespace-qualified name of your class here - if your class is called FooWeight, return "FooWeight" from this method (Xapian::BM25Weight returns "Xapian::BM25Weight" here).

If you don't want to support the remote backend, you can use the default implementation which simply returns an empty string.

Reimplemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, Xapian::IfB2Weight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, ExceptionalWeight, and LazyWeight.

Definition at line 135 of file weight.cc.

Referenced by Xapian::Registry::Internal::add_defaults(), DEFINE_TESTCASE(), Xapian::Registry::register_weighting_scheme(), and RemoteDatabase::set_query().

◆ need_stat()

void Xapian::Weight::need_stat ( stat_flags  flag)
inlineprotected

Tell Xapian that your subclass will want a particular statistic.

Some of the statistics can be costly to fetch or calculate, so Xapian needs to know which are actually going to be used. You should call need_stat() from your constructor for each such statistic.

Parameters
flagThe stat_flags value for a required statistic.

Definition at line 83 of file weight.h.

Referenced by Xapian::BB2Weight::BB2Weight(), Xapian::IfB2Weight::IfB2Weight(), Xapian::IneB2Weight::IneB2Weight(), Xapian::InL2Weight::InL2Weight(), Xapian::PL2PlusWeight::PL2PlusWeight(), Xapian::PL2Weight::PL2Weight(), and Xapian::TfIdfWeight::TfIdfWeight().

◆ operator=()

void Xapian::Weight::operator= ( const Weight )
private

Don't allow assignment.

◆ serialise()

string Xapian::Weight::serialise ( ) const
virtual

Return this object's parameters serialised as a single string.

If you don't want to support the remote backend, you can use the default implementation which simply throws Xapian::UnimplementedError.

Reimplemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, Xapian::IfB2Weight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, and LazyWeight.

Definition at line 141 of file weight.cc.

Referenced by RemoteDatabase::set_query().

◆ unserialise()

Weight * Xapian::Weight::unserialise ( const std::string &  serialised) const
virtual

Unserialise parameters.

This method unserialises parameters serialised by the serialise() method and allocates and returns a new object initialised with them.

If you don't want to support the remote backend, you can use the default implementation which simply throws Xapian::UnimplementedError.

Note that the returned object will be deallocated by Xapian after use with "delete". If you want to handle the deletion in a special way (for example when wrapping the Xapian API for use from another language) then you can define a static operator delete method in your subclass as shown here: https://trac.xapian.org/ticket/554#comment:1

Parameters
serialisedA string containing the serialised parameters.

Reimplemented in MyWeight, Xapian::CoordWeight, Xapian::LMWeight, Xapian::DPHWeight, Xapian::PL2PlusWeight, Xapian::PL2Weight, Xapian::DLHWeight, Xapian::BB2Weight, Xapian::IneB2Weight, Xapian::IfB2Weight, Xapian::InL2Weight, Xapian::TradWeight, Xapian::BM25PlusWeight, Xapian::BM25Weight, Xapian::TfIdfWeight, Xapian::BoolWeight, and LazyWeight.

Definition at line 147 of file weight.cc.

Referenced by RemoteServer::msg_query().

Member Data Documentation

◆ average_length_

Xapian::doclength Xapian::Weight::average_length_
private

The average length of a document in the collection.

Definition at line 112 of file weight.h.

◆ collection_size_

Xapian::doccount Xapian::Weight::collection_size_
private

The number of documents in the collection.

Definition at line 106 of file weight.h.

◆ collectionfreq_

Xapian::termcount Xapian::Weight::collectionfreq_
private

Definition at line 118 of file weight.h.

◆ doclength_lower_bound_

Xapian::termcount Xapian::Weight::doclength_lower_bound_
private

A lower bound on the minimum length of any document in the database.

Definition at line 130 of file weight.h.

◆ doclength_upper_bound_

Xapian::termcount Xapian::Weight::doclength_upper_bound_
private

An upper bound on the maximum length of any document in the database.

Definition at line 133 of file weight.h.

◆ query_length_

Xapian::termcount Xapian::Weight::query_length_
private

The length of the query.

Definition at line 124 of file weight.h.

◆ reltermfreq_

Xapian::doccount Xapian::Weight::reltermfreq_
private

The number of relevant documents which this term indexes.

Definition at line 121 of file weight.h.

◆ rset_size_

Xapian::doccount Xapian::Weight::rset_size_
private

The number of documents marked as relevant.

Definition at line 109 of file weight.h.

◆ stats_needed

stat_flags Xapian::Weight::stats_needed
private

A bitmask of the statistics this weighting scheme needs.

Definition at line 103 of file weight.h.

◆ termfreq_

Xapian::doccount Xapian::Weight::termfreq_
private

The number of documents which this term indexes.

Definition at line 115 of file weight.h.

◆ wdf_upper_bound_

Xapian::termcount Xapian::Weight::wdf_upper_bound_
private

An upper bound on the wdf of this term.

Definition at line 136 of file weight.h.

◆ wqf_

Xapian::termcount Xapian::Weight::wqf_
private

The within-query-frequency of this term.

Definition at line 127 of file weight.h.


The documentation for this class was generated from the following files: