Xapian::BoolWeight Class Reference

#include <weight.h>

Inheritance diagram for Xapian::BoolWeight:

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List of all members.

Public Member Functions

 BoolWeight ()
std::string name () const
std::string serialise () const
BoolWeightunserialise (const std::string &s) const
Xapian::weight get_sumpart (Xapian::termcount wdf, Xapian::termcount doclen) const
Xapian::weight get_maxpart () const
Xapian::weight get_sumextra (Xapian::termcount doclen) const
Xapian::weight get_maxextra () const

Detailed Description

Class implementing a "boolean" weighting scheme.

This weighting scheme gives all documents zero weight.


Constructor & Destructor Documentation

Xapian::BoolWeight::BoolWeight (  )  [inline]

Construct a BoolWeight.


Member Function Documentation

std::string Xapian::BoolWeight::name (  )  const [virtual]

Return the name of this weighting scheme.

This name is used by the remote backend. It is passed 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 in your weighting scheme, you can just implement this to throw Xapian::UnimplementedError.

Implements Xapian::Weight.

std::string Xapian::BoolWeight::serialise (  )  const [virtual]

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

If you don't want to support the remote backend in your weighting scheme, you can just implement this to throw Xapian::UnimplementedError.

Implements Xapian::Weight.

BoolWeight* Xapian::BoolWeight::unserialise ( const std::string &  s  )  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 in your weighting scheme, you can just implement this to throw Xapian::UnimplementedError.

Implements Xapian::Weight.

Xapian::weight Xapian::BoolWeight::get_sumpart ( Xapian::termcount  wdf,
Xapian::termcount  doclen 
) const [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:
wdf The within document frequency of the term in the document.
doclen The document's length (unnormalised).

Implements Xapian::Weight.

Xapian::weight Xapian::BoolWeight::get_maxpart (  )  const [virtual]

Return an upper bound on what get_sumpart() 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.

Implements Xapian::Weight.

Xapian::weight Xapian::BoolWeight::get_sumextra ( Xapian::termcount  doclen  )  const [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:
doclen The document's length (unnormalised).

Implements Xapian::Weight.

Xapian::weight Xapian::BoolWeight::get_maxextra (  )  const [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.

Implements Xapian::Weight.


The documentation for this class was generated from the following file:
Documentation for Xapian (version 1.1.1).
Generated on 10 Jun 2009 by Doxygen 1.5.2.