xapian-core
1.4.26
|
N-way XOR postlist. More...
#include <multixorpostlist.h>
Public Member Functions | |
template<class RandomItor > | |
MultiXorPostList (RandomItor pl_begin, RandomItor pl_end, MultiMatch *matcher_, Xapian::doccount db_size_) | |
Construct from 2 random-access iterators to a container of PostList*, a pointer to the matcher, and the document collection size. More... | |
~MultiXorPostList () | |
Xapian::doccount | get_termfreq_min () const |
Get a lower bound on the number of documents indexed by this term. More... | |
Xapian::doccount | get_termfreq_max () const |
Get an upper 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... | |
TermFreqs | get_termfreq_est_using_stats (const Xapian::Weight::Internal &stats) const |
Get an estimate for the termfreq and reltermfreq, given the stats. More... | |
double | get_maxweight () const |
Return an upper bound on what get_weight() can return. More... | |
Xapian::docid | get_docid () const |
Return the current docid. More... | |
Xapian::termcount | get_doclength () const |
Return the length of current document. More... | |
Xapian::termcount | get_unique_terms () const |
Return the number of unique terms in the current document. More... | |
double | get_weight () const |
Return the weight contribution for the current position. More... | |
bool | at_end () const |
Return true if the current position is past the last entry in this list. More... | |
double | recalc_maxweight () |
Recalculate the upper bound on what get_weight() can return. More... | |
PositionList * | read_position_list () |
Read the position list for the term in the current document and return a pointer to it (owned by the PostList). More... | |
PostList * | next (double w_min) |
Advance the current position to the next document in the postlist. More... | |
PostList * | skip_to (Xapian::docid, double w_min) |
Skip forward to the specified docid. More... | |
std::string | get_description () const |
Return a string description of this object. More... | |
Xapian::termcount | get_wdf () const |
get_wdf() for MultiXorPostlists returns the sum of the wdfs of the sub postlists which match the current docid. More... | |
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 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 PositionList * | open_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 Internal * | check (Xapian::docid did, double w_min, bool &valid) |
Check if the specified docid occurs in this postlist. More... | |
Internal * | next () |
Advance the current position to the next document in the postlist. More... | |
Internal * | skip_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 Member Functions | |
void | operator= (const MultiXorPostList &) |
Don't allow assignment. More... | |
MultiXorPostList (const MultiXorPostList &) | |
Don't allow copying. More... | |
void | erase_sublist (size_t i) |
Erase a sub-postlist. More... | |
Private Attributes | |
Xapian::docid | did |
The current docid, or zero if we haven't started or are at_end. More... | |
size_t | n_kids |
The number of sub-postlists. More... | |
PostList ** | plist |
Array of pointers to sub-postlists. More... | |
double | max_total |
Total maximum weight the XOR could possibly return. More... | |
Xapian::doccount | db_size |
The number of documents in the database. More... | |
MultiMatch * | matcher |
Pointer to the matcher object, so we can report pruning. More... | |
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... | |
N-way XOR postlist.
Definition at line 32 of file multixorpostlist.h.
|
private |
Don't allow copying.
|
inline |
Construct from 2 random-access iterators to a container of PostList*, a pointer to the matcher, and the document collection size.
Definition at line 72 of file multixorpostlist.h.
References at_end(), get_docid(), get_doclength(), get_maxweight(), get_termfreq_est(), get_termfreq_est_using_stats(), get_termfreq_max(), get_termfreq_min(), get_unique_terms(), get_weight(), n_kids, recalc_maxweight(), and ~MultiXorPostList().
MultiXorPostList::~MultiXorPostList | ( | ) |
Definition at line 33 of file multixorpostlist.cc.
Referenced by MultiXorPostList().
|
virtual |
Return true if the current position is past the last entry in this list.
Implements Xapian::PostingIterator::Internal.
Definition at line 248 of file multixorpostlist.cc.
Referenced by MultiXorPostList().
|
virtual |
Count the number of leaf subqueries which match at the current position.
Reimplemented from Xapian::PostingIterator::Internal.
Definition at line 396 of file multixorpostlist.cc.
Referenced by read_position_list().
|
inlineprivate |
Erase a sub-postlist.
Definition at line 58 of file multixorpostlist.h.
References n_kids, and MultiMatch::recalc_maxweight().
|
virtual |
Return a string description of this object.
Implements Xapian::PostingIterator::Internal.
Definition at line 372 of file multixorpostlist.cc.
Referenced by read_position_list().
|
virtual |
Return the current docid.
Implements Xapian::PostingIterator::Internal.
Definition at line 190 of file multixorpostlist.cc.
Referenced by MultiXorPostList().
|
virtual |
Return the length of current document.
Implements Xapian::PostingIterator::Internal.
Definition at line 196 of file multixorpostlist.cc.
References Assert, and AssertEq.
Referenced by MultiXorPostList().
|
virtual |
Return an upper bound on what get_weight() can return.
Implements Xapian::PostingIterator::Internal.
Definition at line 183 of file multixorpostlist.cc.
References LOGCALL, and RETURN.
Referenced by MultiXorPostList().
|
virtual |
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 121 of file multixorpostlist.cc.
References Assert, and LOGCALL.
Referenced by MultiXorPostList().
|
virtual |
Get an estimate for the termfreq and reltermfreq, given the stats.
The frequencies may be for a combination of databases, or for just the relevant documents, so the results need not lie in the bounds given by get_termfreq_min() and get_termfreq_max().
Reimplemented from Xapian::PostingIterator::Internal.
Definition at line 139 of file multixorpostlist.cc.
References Assert, Xapian::Weight::Internal::collection_size, TermFreqs::collfreq, LOGCALL, TermFreqs::reltermfreq, RETURN, Xapian::Weight::Internal::rset_size, TermFreqs::termfreq, Xapian::Weight::Internal::total_length, and usual.
Referenced by MultiXorPostList().
|
virtual |
Get an upper bound on the number of documents indexed by this term.
Implements Xapian::PostingIterator::Internal.
Definition at line 93 of file multixorpostlist.cc.
Referenced by MultiXorPostList().
|
virtual |
Get a lower bound on the number of documents indexed by this term.
Implements Xapian::PostingIterator::Internal.
Definition at line 44 of file multixorpostlist.cc.
Referenced by MultiXorPostList().
|
virtual |
Return the number of unique terms in the current document.
Implements Xapian::PostingIterator::Internal.
Definition at line 216 of file multixorpostlist.cc.
References Assert, and AssertEq.
Referenced by MultiXorPostList().
|
virtual |
get_wdf() for MultiXorPostlists returns the sum of the wdfs of the sub postlists which match the current docid.
The wdf isn't really meaningful in many situations, but if the lists are being combined as a synonym we want the sum of the wdfs, so we do that in general.
Reimplemented from Xapian::PostingIterator::Internal.
Definition at line 385 of file multixorpostlist.cc.
Referenced by read_position_list().
|
virtual |
Return the weight contribution for the current position.
Implements Xapian::PostingIterator::Internal.
Definition at line 236 of file multixorpostlist.cc.
References Assert.
Referenced by MultiXorPostList().
|
virtual |
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.
w_min | The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore). |
Implements Xapian::PostingIterator::Internal.
Definition at line 273 of file multixorpostlist.cc.
References LOGCALL, Xapian::PostingIterator::Internal::next(), Xapian::PostingIterator::Internal::recalc_maxweight(), and RETURN.
|
private |
Don't allow assignment.
|
inlinevirtual |
Read the position list for the term in the current document and return a pointer to it (owned by the PostList).
The default implementation throws Xapian::UnimplementedError.
Reimplemented from Xapian::PostingIterator::Internal.
Definition at line 106 of file multixorpostlist.h.
References count_matching_subqs(), get_description(), get_wdf(), Xapian::PostingIterator::Internal::next(), and skip_to().
|
virtual |
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 254 of file multixorpostlist.cc.
References LOGCALL, and RETURN.
Referenced by MultiXorPostList().
|
virtual |
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).
w_min | The minimum weight contribution that is needed (this is just a hint which PostList subclasses may ignore). |
Implements Xapian::PostingIterator::Internal.
Definition at line 322 of file multixorpostlist.cc.
References AssertEq, LOGCALL, Xapian::PostingIterator::Internal::recalc_maxweight(), RETURN, and Xapian::PostingIterator::Internal::skip_to().
Referenced by read_position_list().
|
private |
The number of documents in the database.
Definition at line 52 of file multixorpostlist.h.
|
private |
The current docid, or zero if we haven't started or are at_end.
Definition at line 40 of file multixorpostlist.h.
|
private |
Pointer to the matcher object, so we can report pruning.
Definition at line 55 of file multixorpostlist.h.
|
private |
Total maximum weight the XOR could possibly return.
Definition at line 49 of file multixorpostlist.h.
|
private |
The number of sub-postlists.
Definition at line 43 of file multixorpostlist.h.
Referenced by erase_sublist(), and MultiXorPostList().
|
private |
Array of pointers to sub-postlists.
Definition at line 46 of file multixorpostlist.h.