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<a class="el" href="namespaceXapian.html">Xapian</a>::<a class="el" href="classXapian_1_1BoolWeight.html">BoolWeight</a></div>
<h1>Xapian::BoolWeight Class Reference</h1><!-- doxytag: class="Xapian::BoolWeight" --><!-- doxytag: inherits="Xapian::Weight" -->Boolean weighting scheme (everything gets 0).
<a href="#_details">More...</a>
<p>
Inheritance diagram for Xapian::BoolWeight:<p><center><img src="classXapian_1_1BoolWeight__inherit__graph.png" border="0" usemap="#Xapian_1_1BoolWeight__inherit__map" alt="Inheritance graph"></center>
<map name="Xapian_1_1BoolWeight__inherit__map">
<area shape="rect" href="classXapian_1_1Weight.html" title="Abstract base class for weighting schemes." alt="" coords="19,7,133,33"></map>
<center><font size="2">[<a href="graph_legend.html">legend</a>]</font></center><a href="classXapian_1_1BoolWeight-members.html">List of all members.</a><table border="0" cellpadding="0" cellspacing="0">
<tr><td></td></tr>
<tr><td colspan="2"><br><h2>Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="classXapian_1_1BoolWeight.html">BoolWeight</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#dd54a72ea54d4d9ee7863c104a5404d3">clone</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Return a new weight object of this type. <a href="#dd54a72ea54d4d9ee7863c104a5404d3"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#f6afab51d1849ebdbd429c7094e047f8">name</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Name of the weighting scheme. <a href="#f6afab51d1849ebdbd429c7094e047f8"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#ecaa9899faaf1dc228abf8f086d7498a">serialise</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Serialise object parameters into a string. <a href="#ecaa9899faaf1dc228abf8f086d7498a"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="classXapian_1_1BoolWeight.html">BoolWeight</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#e7eed49260e94c0f479b59c109bc744d">unserialise</a> (const std::string &s) const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Create object given string serialisation returned by <a class="el" href="classXapian_1_1BoolWeight.html#ecaa9899faaf1dc228abf8f086d7498a" title="Serialise object parameters into a string.">serialise()</a>. <a href="#e7eed49260e94c0f479b59c109bc744d"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#d4f5043cab9fabb83e91fb66b2a3995f">get_sumpart</a> (<a class="el" href="namespaceXapian.html#3261017447607738e49eae6a2a4f5eec">Xapian::termcount</a> wdf, <a class="el" href="namespaceXapian.html#6c1c4bfd0b540caccbb5179976ebf792">Xapian::doclength</a> len) const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get a weight which is part of the sum over terms being performed. <a href="#d4f5043cab9fabb83e91fb66b2a3995f"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#f209ecd61f299feabcb1d996c2b6df28">get_maxpart</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Gets the maximum value that <a class="el" href="classXapian_1_1BoolWeight.html#d4f5043cab9fabb83e91fb66b2a3995f" title="Get a weight which is part of the sum over terms being performed.">get_sumpart()</a> may return. <a href="#f209ecd61f299feabcb1d996c2b6df28"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#7713c9aee47dd4fb1f97f3cb9c0011e4">get_sumextra</a> (<a class="el" href="namespaceXapian.html#6c1c4bfd0b540caccbb5179976ebf792">Xapian::doclength</a> len) const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Get an extra weight for a document to add to the sum calculated over the query terms. <a href="#7713c9aee47dd4fb1f97f3cb9c0011e4"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#6ad1e00c24065a9cab0a70dd56fcf7d4">get_maxextra</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Gets the maximum value that <a class="el" href="classXapian_1_1BoolWeight.html#7713c9aee47dd4fb1f97f3cb9c0011e4" title="Get an extra weight for a document to add to the sum calculated over the query terms...">get_sumextra()</a> may return. <a href="#6ad1e00c24065a9cab0a70dd56fcf7d4"></a><br></td></tr>
<tr><td class="memItemLeft" nowrap align="right" valign="top">bool </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BoolWeight.html#4a791e5299d29a71f5cac62bbf7ecad1">get_sumpart_needs_doclength</a> () const</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">return false if the weight object doesn't need doclength <a href="#4a791e5299d29a71f5cac62bbf7ecad1"></a><br></td></tr>
</table>
<hr><a name="_details"></a><h2>Detailed Description</h2>
Boolean weighting scheme (everything gets 0).
<p>
<hr><h2>Member Function Documentation</h2>
<a class="anchor" name="dd54a72ea54d4d9ee7863c104a5404d3"></a><!-- doxytag: member="Xapian::BoolWeight::clone" ref="dd54a72ea54d4d9ee7863c104a5404d3" args="() const" -->
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<td class="memname"><a class="el" href="classXapian_1_1BoolWeight.html">BoolWeight</a>* Xapian::BoolWeight::clone </td>
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<td width="100%"> const<code> [virtual]</code></td>
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<p>
Return a new weight object of this type.
<p>
A subclass called FooWeight taking parameters param1 and param2 should implement this as:<p>
virtual FooWeight * <a class="el" href="classXapian_1_1BoolWeight.html#dd54a72ea54d4d9ee7863c104a5404d3" title="Return a new weight object of this type.">clone() const</a> { return new FooWeight(param1, param2); }
<p>
Implements <a class="el" href="classXapian_1_1Weight.html">Xapian::Weight</a>.
</div>
</div><p>
<a class="anchor" name="f6afab51d1849ebdbd429c7094e047f8"></a><!-- doxytag: member="Xapian::BoolWeight::name" ref="f6afab51d1849ebdbd429c7094e047f8" args="() const" -->
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<td class="memname">std::string Xapian::BoolWeight::name </td>
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<td width="100%"> const<code> [virtual]</code></td>
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<p>
Name of the weighting scheme.
<p>
If the subclass is called FooWeight, this should return "Foo".
<p>
Implements <a class="el" href="classXapian_1_1Weight.html#b0a873c16f02bcf9ea54b632b7c8600a">Xapian::Weight</a>.
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<a class="anchor" name="ecaa9899faaf1dc228abf8f086d7498a"></a><!-- doxytag: member="Xapian::BoolWeight::serialise" ref="ecaa9899faaf1dc228abf8f086d7498a" args="() const" -->
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<td class="memname">std::string Xapian::BoolWeight::serialise </td>
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<td> ) </td>
<td width="100%"> const<code> [virtual]</code></td>
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<p>
Serialise object parameters into a string.
<p>
<p>
Implements <a class="el" href="classXapian_1_1Weight.html#b2ff0584c32e9db9f52dafed9e4e2bcf">Xapian::Weight</a>.
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<a class="anchor" name="e7eed49260e94c0f479b59c109bc744d"></a><!-- doxytag: member="Xapian::BoolWeight::unserialise" ref="e7eed49260e94c0f479b59c109bc744d" args="(const std::string &s) const" -->
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<td class="memname"><a class="el" href="classXapian_1_1BoolWeight.html">BoolWeight</a>* Xapian::BoolWeight::unserialise </td>
<td>(</td>
<td class="paramtype">const std::string & </td>
<td class="paramname"> <em>s</em> </td>
<td> ) </td>
<td width="100%"> const<code> [virtual]</code></td>
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Create object given string serialisation returned by <a class="el" href="classXapian_1_1BoolWeight.html#ecaa9899faaf1dc228abf8f086d7498a" title="Serialise object parameters into a string.">serialise()</a>.
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<p>
Implements <a class="el" href="classXapian_1_1Weight.html#c6948bf58e52443ca6c8d5547bf14d14">Xapian::Weight</a>.
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<a class="anchor" name="d4f5043cab9fabb83e91fb66b2a3995f"></a><!-- doxytag: member="Xapian::BoolWeight::get_sumpart" ref="d4f5043cab9fabb83e91fb66b2a3995f" args="(Xapian::termcount wdf, Xapian::doclength len) const" -->
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<td class="memname"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> Xapian::BoolWeight::get_sumpart </td>
<td>(</td>
<td class="paramtype"><a class="el" href="namespaceXapian.html#3261017447607738e49eae6a2a4f5eec">Xapian::termcount</a> </td>
<td class="paramname"> <em>wdf</em>, </td>
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<td class="paramtype"><a class="el" href="namespaceXapian.html#6c1c4bfd0b540caccbb5179976ebf792">Xapian::doclength</a> </td>
<td class="paramname"> <em>len</em></td><td> </td>
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<td></td><td></td><td width="100%"> const<code> [virtual]</code></td>
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<p>
Get a weight which is part of the sum over terms being performed.
<p>
This returns a weight for a given term and document. These weights are summed to give a total weight for the document.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>wdf</em> </td><td>the within document frequency of the term. </td></tr>
<tr><td valign="top"></td><td valign="top"><em>len</em> </td><td>the (unnormalised) document length. </td></tr>
</table>
</dl>
<p>
Implements <a class="el" href="classXapian_1_1Weight.html#35ac7463961ccfcfa7ff6abc170135f8">Xapian::Weight</a>.
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<a class="anchor" name="f209ecd61f299feabcb1d996c2b6df28"></a><!-- doxytag: member="Xapian::BoolWeight::get_maxpart" ref="f209ecd61f299feabcb1d996c2b6df28" args="() const" -->
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<td class="memname"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> Xapian::BoolWeight::get_maxpart </td>
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<p>
Gets the maximum value that <a class="el" href="classXapian_1_1BoolWeight.html#d4f5043cab9fabb83e91fb66b2a3995f" title="Get a weight which is part of the sum over terms being performed.">get_sumpart()</a> may return.
<p>
This is used in optimising searches, by having the postlist tree decay appropriately when parts of it can have limited, or no, further effect.
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Implements <a class="el" href="classXapian_1_1Weight.html#029bd952184c78f75126227de336f3f6">Xapian::Weight</a>.
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<a class="anchor" name="7713c9aee47dd4fb1f97f3cb9c0011e4"></a><!-- doxytag: member="Xapian::BoolWeight::get_sumextra" ref="7713c9aee47dd4fb1f97f3cb9c0011e4" args="(Xapian::doclength len) const" -->
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<td class="memname"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> Xapian::BoolWeight::get_sumextra </td>
<td>(</td>
<td class="paramtype"><a class="el" href="namespaceXapian.html#6c1c4bfd0b540caccbb5179976ebf792">Xapian::doclength</a> </td>
<td class="paramname"> <em>len</em> </td>
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<td width="100%"> const<code> [virtual]</code></td>
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<p>
Get an extra weight for a document to add to the sum calculated over the query terms.
<p>
This returns a weight for a given document, and is used by some weighting schemes to account for influence such as document length.<p>
<dl compact><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>len</em> </td><td>the (unnormalised) document length. </td></tr>
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Implements <a class="el" href="classXapian_1_1Weight.html#9fec5777ea998c2925b0960e3d9ca31c">Xapian::Weight</a>.
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<a class="anchor" name="6ad1e00c24065a9cab0a70dd56fcf7d4"></a><!-- doxytag: member="Xapian::BoolWeight::get_maxextra" ref="6ad1e00c24065a9cab0a70dd56fcf7d4" args="() const" -->
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<td class="memname"><a class="el" href="namespaceXapian.html#ee1bece7207c349621963d7f584dd98b">Xapian::weight</a> Xapian::BoolWeight::get_maxextra </td>
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<td width="100%"> const<code> [virtual]</code></td>
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<p>
Gets the maximum value that <a class="el" href="classXapian_1_1BoolWeight.html#7713c9aee47dd4fb1f97f3cb9c0011e4" title="Get an extra weight for a document to add to the sum calculated over the query terms...">get_sumextra()</a> may return.
<p>
This is used in optimising searches.
<p>
Implements <a class="el" href="classXapian_1_1Weight.html#158796278206334879e4861d7ebc1040">Xapian::Weight</a>.
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<a class="anchor" name="4a791e5299d29a71f5cac62bbf7ecad1"></a><!-- doxytag: member="Xapian::BoolWeight::get_sumpart_needs_doclength" ref="4a791e5299d29a71f5cac62bbf7ecad1" args="() const" -->
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<td class="memname">bool Xapian::BoolWeight::get_sumpart_needs_doclength </td>
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<td width="100%"> const<code> [virtual]</code></td>
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<p>
return false if the weight object doesn't need doclength
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<p>
Reimplemented from <a class="el" href="classXapian_1_1Weight.html#057ce24c2d3a54dc6a6b3127d064ce9f">Xapian::Weight</a>.
</div>
</div><p>
<hr>The documentation for this class was generated from the following file:<ul>
<li>xapian/<a class="el" href="enquire_8h.html">enquire.h</a></ul>
<hr>
<address><small>
Documentation for Xapian (version 1.0.21).<br>
Generated on 18 Jun 2010 by
<a href="http://www.doxygen.org/">Doxygen 1.5.2</a>.
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