xapian-core  1.4.19
Public Member Functions | Private Attributes | List of all members
ExtraWeightPostList Class Reference

A postlist which adds on an extra weight contribution. More...

#include <extraweightpostlist.h>

+ Inheritance diagram for ExtraWeightPostList:
+ Collaboration diagram for ExtraWeightPostList:

Public Member Functions

Xapian::doccount get_termfreq_max () const
 Get an upper bound on the number of documents indexed by this term. More...
 
Xapian::doccount get_termfreq_min () const
 Get a lower bound on the number of documents indexed by this term. More...
 
Xapian::doccount get_termfreq_est () const
 Get an estimate of the number of documents indexed by this term. More...
 
Xapian::docid get_docid () const
 Return the current docid. More...
 
double get_weight () const
 Return the weight contribution for the current position. More...
 
double get_maxweight () const
 Return an upper bound on what get_weight() can return. More...
 
double recalc_maxweight ()
 Recalculate the upper bound on what get_weight() can return. More...
 
PostListnext (double w_min)
 Advance the current position to the next document in the postlist. More...
 
PostListskip_to (Xapian::docid did, double w_min)
 Skip forward to the specified docid. More...
 
bool at_end () const
 Return true if the current position is past the last entry in this list. More...
 
std::string get_description () const
 Return a string description of this object. More...
 
virtual Xapian::termcount get_doclength () const
 Return the document length of the document the current term comes from. More...
 
virtual Xapian::termcount get_unique_terms () const
 Return the number of unique terms in the current document. More...
 
 ExtraWeightPostList (PostList *pl_, Xapian::Weight *wt_, MultiMatch *matcher_)
 
 ~ExtraWeightPostList ()
 
Xapian::termcount count_matching_subqs () const
 Count the number of leaf subqueries which match at the current position. More...
 
- Public Member Functions inherited from Xapian::PostingIterator::Internal
virtual ~Internal ()
 We have virtual methods and want to be able to delete derived classes using a pointer to the base class, so we need a virtual destructor. More...
 
virtual TermFreqs get_termfreq_est_using_stats (const Xapian::Weight::Internal &stats) const
 Get an estimate for the termfreq and reltermfreq, given the stats. More...
 
virtual Xapian::termcount get_wdf () const
 Return the wdf for the document at the current position. More...
 
virtual const std::string * get_sort_key () const
 
virtual const std::string * get_collapse_key () const
 If the collapse key is already known, return it. More...
 
virtual PositionListread_position_list ()
 Read the position list for the term in the current document and return a pointer to it (owned by the PostList). More...
 
virtual PositionListopen_position_list () const
 Read the position list for the term in the current document and return a pointer to it (not owned by the PostList). More...
 
virtual Internalcheck (Xapian::docid did, double w_min, bool &valid)
 Check if the specified docid occurs in this postlist. More...
 
Internalnext ()
 Advance the current position to the next document in the postlist. More...
 
Internalskip_to (Xapian::docid did)
 Skip forward to the specified docid. More...
 
virtual void gather_position_lists (OrPositionList *orposlist)
 Gather PositionList* objects for a subtree. More...
 
- Public Member Functions inherited from Xapian::Internal::intrusive_base
 intrusive_base ()
 Construct with no references. More...
 

Private Attributes

PostListpl
 
Xapian::Weightwt
 
MultiMatchmatcher
 
double max_weight
 

Additional Inherited Members

- Public Attributes inherited from Xapian::Internal::intrusive_base
unsigned _refs
 Reference count. More...
 
- Protected Member Functions inherited from Xapian::PostingIterator::Internal
 Internal ()
 Only constructable as a base class for derived classes. More...
 

Detailed Description

A postlist which adds on an extra weight contribution.

Definition at line 35 of file extraweightpostlist.h.

Constructor & Destructor Documentation

◆ ExtraWeightPostList()

ExtraWeightPostList::ExtraWeightPostList ( PostList pl_,
Xapian::Weight wt_,
MultiMatch matcher_ 
)
inline

Definition at line 110 of file extraweightpostlist.h.

◆ ~ExtraWeightPostList()

ExtraWeightPostList::~ExtraWeightPostList ( )
inline

Definition at line 116 of file extraweightpostlist.h.

Member Function Documentation

◆ at_end()

bool ExtraWeightPostList::at_end ( ) const
inlinevirtual

Return true if the current position is past the last entry in this list.

Implements Xapian::PostingIterator::Internal.

Definition at line 93 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::at_end().

◆ count_matching_subqs()

Xapian::termcount ExtraWeightPostList::count_matching_subqs ( ) const
inlinevirtual

Count the number of leaf subqueries which match at the current position.

Reimplemented from Xapian::PostingIterator::Internal.

Definition at line 121 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::count_matching_subqs().

◆ get_description()

std::string ExtraWeightPostList::get_description ( ) const
inlinevirtual

Return a string description of this object.

Implements Xapian::PostingIterator::Internal.

Definition at line 95 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_description().

◆ get_docid()

Xapian::docid ExtraWeightPostList::get_docid ( ) const
inlinevirtual

Return the current docid.

Implements Xapian::PostingIterator::Internal.

Definition at line 53 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_docid().

◆ get_doclength()

virtual Xapian::termcount ExtraWeightPostList::get_doclength ( ) const
inlinevirtual

Return the document length of the document the current term comes from.

Implements Xapian::PostingIterator::Internal.

Definition at line 102 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_doclength().

◆ get_maxweight()

double ExtraWeightPostList::get_maxweight ( ) const
inlinevirtual

Return an upper bound on what get_weight() can return.

Implements Xapian::PostingIterator::Internal.

Definition at line 65 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_maxweight().

◆ get_termfreq_est()

Xapian::doccount ExtraWeightPostList::get_termfreq_est ( ) const
inlinevirtual

Get an estimate of the number of documents indexed by this term.

It should always be true that: get_termfreq_min() <= get_termfreq_est() <= get_termfreq_max()

Implements Xapian::PostingIterator::Internal.

Definition at line 49 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_est().

◆ get_termfreq_max()

Xapian::doccount ExtraWeightPostList::get_termfreq_max ( ) const
inlinevirtual

Get an upper bound on the number of documents indexed by this term.

Implements Xapian::PostingIterator::Internal.

Definition at line 43 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_max().

◆ get_termfreq_min()

Xapian::doccount ExtraWeightPostList::get_termfreq_min ( ) const
inlinevirtual

Get a lower bound on the number of documents indexed by this term.

Implements Xapian::PostingIterator::Internal.

Definition at line 46 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_termfreq_min().

◆ get_unique_terms()

virtual Xapian::termcount ExtraWeightPostList::get_unique_terms ( ) const
inlinevirtual

Return the number of unique terms in the current document.

Implements Xapian::PostingIterator::Internal.

Definition at line 106 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::get_unique_terms().

◆ get_weight()

double ExtraWeightPostList::get_weight ( ) const
inlinevirtual

◆ next()

PostList* ExtraWeightPostList::next ( double  w_min)
inlinevirtual

Advance the current position to the next document in the postlist.

The list starts before the first entry in the list, so next(), skip_to() or check() must be called before any methods which need the context of the current position.

Parameters
w_minThe minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).
Returns
If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::PostingIterator::Internal.

Definition at line 73 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::next(), and MultiMatch::recalc_maxweight().

◆ recalc_maxweight()

double ExtraWeightPostList::recalc_maxweight ( )
inlinevirtual

Recalculate the upper bound on what get_weight() can return.

If the tree has pruned, get_maxweight() may use cached values. Calling this method instead forces a full recalculation.

Note that this method may be called after the postlist has reached the end. In this situation, the method should return 0.

Implements Xapian::PostingIterator::Internal.

Definition at line 69 of file extraweightpostlist.h.

References Xapian::PostingIterator::Internal::recalc_maxweight().

◆ skip_to()

PostList* ExtraWeightPostList::skip_to ( Xapian::docid  did,
double  w_min 
)
inlinevirtual

Skip forward to the specified docid.

If the specified docid isn't in the list, position ourselves on the first document after it (or at_end() if no greater docids are present).

Parameters
w_minThe minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore).
Returns
If a non-NULL pointer is returned, then the caller should substitute the returned pointer for its pointer to us, and then delete us. This "pruning" can only happen for a non-leaf subclass of this class.

Implements Xapian::PostingIterator::Internal.

Definition at line 83 of file extraweightpostlist.h.

References MultiMatch::recalc_maxweight(), and Xapian::PostingIterator::Internal::skip_to().

Member Data Documentation

◆ matcher

MultiMatch* ExtraWeightPostList::matcher
private

Definition at line 39 of file extraweightpostlist.h.

◆ max_weight

double ExtraWeightPostList::max_weight
private

Definition at line 40 of file extraweightpostlist.h.

◆ pl

PostList* ExtraWeightPostList::pl
private

Definition at line 37 of file extraweightpostlist.h.

◆ wt

Xapian::Weight* ExtraWeightPostList::wt
private

Definition at line 38 of file extraweightpostlist.h.


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