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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<title>Xapian: API Documentation: Xapian::BM25PlusWeight Class Reference</title>
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 <span id="projectnumber">1.4.22</span>
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<li class="navelem"><a class="el" href="namespaceXapian.html">Xapian</a></li><li class="navelem"><a class="el" href="classXapian_1_1BM25PlusWeight.html">BM25PlusWeight</a></li> </ul>
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<a href="#pub-methods">Public Member Functions</a> |
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<div class="headertitle"><div class="title">Xapian::BM25PlusWeight Class Reference</div></div>
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<p><a class="el" href="classXapian_1_1Weight.html" title="Abstract base class for weighting schemes.">Xapian::Weight</a> subclass implementing the BM25+ probabilistic formula.
<a href="classXapian_1_1BM25PlusWeight.html#details">More...</a></p>
<p><code>#include <weight.h></code></p>
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<img id="dynsection-0-trigger" src="closed.png" alt="+"/> Inheritance diagram for Xapian::BM25PlusWeight:</div>
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<area shape="rect" title="Xapian::Weight subclass implementing the BM25+ probabilistic formula." alt="" coords="5,80,191,107"/>
<area shape="rect" href="classXapian_1_1Weight.html" title="Abstract base class for weighting schemes." alt="" coords="37,5,159,32"/>
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<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="pub-methods" name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr class="memitem:ae42d928ab5f029167d227eefaaa7bc88"><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#ae42d928ab5f029167d227eefaaa7bc88">BM25PlusWeight</a> (double k1, double k2, double k3, double b, double min_normlen, double delta)</td></tr>
<tr class="memdesc:ae42d928ab5f029167d227eefaaa7bc88"><td class="mdescLeft"> </td><td class="mdescRight">Construct a <a class="el" href="classXapian_1_1BM25PlusWeight.html" title="Xapian::Weight subclass implementing the BM25+ probabilistic formula.">BM25PlusWeight</a>. <a href="classXapian_1_1BM25PlusWeight.html#ae42d928ab5f029167d227eefaaa7bc88">More...</a><br /></td></tr>
<tr class="separator:ae42d928ab5f029167d227eefaaa7bc88"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a456922fa3c01a6dcdca7c2d283786141"><td class="memItemLeft" align="right" valign="top">std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#a456922fa3c01a6dcdca7c2d283786141">name</a> () const</td></tr>
<tr class="memdesc:a456922fa3c01a6dcdca7c2d283786141"><td class="mdescLeft"> </td><td class="mdescRight">Return the name of this weighting scheme. <a href="classXapian_1_1BM25PlusWeight.html#a456922fa3c01a6dcdca7c2d283786141">More...</a><br /></td></tr>
<tr class="separator:a456922fa3c01a6dcdca7c2d283786141"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a637b5ea25f921f36dfb8b36aafb407b4"><td class="memItemLeft" align="right" valign="top">std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#a637b5ea25f921f36dfb8b36aafb407b4">serialise</a> () const</td></tr>
<tr class="memdesc:a637b5ea25f921f36dfb8b36aafb407b4"><td class="mdescLeft"> </td><td class="mdescRight">Return this object's parameters serialised as a single string. <a href="classXapian_1_1BM25PlusWeight.html#a637b5ea25f921f36dfb8b36aafb407b4">More...</a><br /></td></tr>
<tr class="separator:a637b5ea25f921f36dfb8b36aafb407b4"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a9d1e21b49c34b415e40b30c9bf3435b1"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classXapian_1_1BM25PlusWeight.html">BM25PlusWeight</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#a9d1e21b49c34b415e40b30c9bf3435b1">unserialise</a> (const std::string &serialised) const</td></tr>
<tr class="memdesc:a9d1e21b49c34b415e40b30c9bf3435b1"><td class="mdescLeft"> </td><td class="mdescRight">Unserialise parameters. <a href="classXapian_1_1BM25PlusWeight.html#a9d1e21b49c34b415e40b30c9bf3435b1">More...</a><br /></td></tr>
<tr class="separator:a9d1e21b49c34b415e40b30c9bf3435b1"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aa38b5f0fc4dbf45eb876ca3552dc7871"><td class="memItemLeft" align="right" valign="top">double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#aa38b5f0fc4dbf45eb876ca3552dc7871">get_sumpart</a> (<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> wdf, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> doclen, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> uniqterm) const</td></tr>
<tr class="memdesc:aa38b5f0fc4dbf45eb876ca3552dc7871"><td class="mdescLeft"> </td><td class="mdescRight">Calculate the weight contribution for this object's term to a document. <a href="classXapian_1_1BM25PlusWeight.html#aa38b5f0fc4dbf45eb876ca3552dc7871">More...</a><br /></td></tr>
<tr class="separator:aa38b5f0fc4dbf45eb876ca3552dc7871"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aa31188c0036ccaf9a0c00556a8dfb8bb"><td class="memItemLeft" align="right" valign="top">double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#aa31188c0036ccaf9a0c00556a8dfb8bb">get_maxpart</a> () const</td></tr>
<tr class="memdesc:aa31188c0036ccaf9a0c00556a8dfb8bb"><td class="mdescLeft"> </td><td class="mdescRight">Return an upper bound on what <a class="el" href="classXapian_1_1BM25PlusWeight.html#aa38b5f0fc4dbf45eb876ca3552dc7871" title="Calculate the weight contribution for this object's term to a document.">get_sumpart()</a> can return for any document. <a href="classXapian_1_1BM25PlusWeight.html#aa31188c0036ccaf9a0c00556a8dfb8bb">More...</a><br /></td></tr>
<tr class="separator:aa31188c0036ccaf9a0c00556a8dfb8bb"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a61ead2c8f139895fc69c10f2c9952e59"><td class="memItemLeft" align="right" valign="top">double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#a61ead2c8f139895fc69c10f2c9952e59">get_sumextra</a> (<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> doclen, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> uniqterms) const</td></tr>
<tr class="memdesc:a61ead2c8f139895fc69c10f2c9952e59"><td class="mdescLeft"> </td><td class="mdescRight">Calculate the term-independent weight component for a document. <a href="classXapian_1_1BM25PlusWeight.html#a61ead2c8f139895fc69c10f2c9952e59">More...</a><br /></td></tr>
<tr class="separator:a61ead2c8f139895fc69c10f2c9952e59"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ab326326a2a50cc91e066ad83cdf507eb"><td class="memItemLeft" align="right" valign="top">double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1BM25PlusWeight.html#ab326326a2a50cc91e066ad83cdf507eb">get_maxextra</a> () const</td></tr>
<tr class="memdesc:ab326326a2a50cc91e066ad83cdf507eb"><td class="mdescLeft"> </td><td class="mdescRight">Return an upper bound on what <a class="el" href="classXapian_1_1BM25PlusWeight.html#a61ead2c8f139895fc69c10f2c9952e59" title="Calculate the term-independent weight component for a document.">get_sumextra()</a> can return for any document. <a href="classXapian_1_1BM25PlusWeight.html#ab326326a2a50cc91e066ad83cdf507eb">More...</a><br /></td></tr>
<tr class="separator:ab326326a2a50cc91e066ad83cdf507eb"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="inherit_header pub_methods_classXapian_1_1Weight"><td colspan="2" onclick="javascript:toggleInherit('pub_methods_classXapian_1_1Weight')"><img src="closed.png" alt="-"/> Public Member Functions inherited from <a class="el" href="classXapian_1_1Weight.html">Xapian::Weight</a></td></tr>
<tr class="memitem:a48e8f4d351f2a090bcec111513833e0f inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a48e8f4d351f2a090bcec111513833e0f" name="a48e8f4d351f2a090bcec111513833e0f"></a>
 </td><td class="memItemRight" valign="bottom"><b>Weight</b> ()</td></tr>
<tr class="memdesc:a48e8f4d351f2a090bcec111513833e0f inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Default constructor, needed by subclass constructors. <br /></td></tr>
<tr class="separator:a48e8f4d351f2a090bcec111513833e0f inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:adcc0dd3e0c762597e89720043440a0bd inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="adcc0dd3e0c762597e89720043440a0bd" name="adcc0dd3e0c762597e89720043440a0bd"></a>
virtual </td><td class="memItemRight" valign="bottom"><b>~Weight</b> ()</td></tr>
<tr class="memdesc:adcc0dd3e0c762597e89720043440a0bd inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Virtual destructor, because we have virtual methods. <br /></td></tr>
<tr class="separator:adcc0dd3e0c762597e89720043440a0bd inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aa3124ab7eda6beb358b7e98570386972 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="classXapian_1_1Weight.html">Weight</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#aa3124ab7eda6beb358b7e98570386972">clone</a> () const =0</td></tr>
<tr class="memdesc:aa3124ab7eda6beb358b7e98570386972 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Clone this object. <a href="classXapian_1_1Weight.html#aa3124ab7eda6beb358b7e98570386972">More...</a><br /></td></tr>
<tr class="separator:aa3124ab7eda6beb358b7e98570386972 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a6106970d1a1e9600c9b32cc6ec96bf6b inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a6106970d1a1e9600c9b32cc6ec96bf6b">name</a> () const</td></tr>
<tr class="memdesc:a6106970d1a1e9600c9b32cc6ec96bf6b inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Return the name of this weighting scheme. <a href="classXapian_1_1Weight.html#a6106970d1a1e9600c9b32cc6ec96bf6b">More...</a><br /></td></tr>
<tr class="separator:a6106970d1a1e9600c9b32cc6ec96bf6b inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a5162368a30a0fc10d69359665b5d8e0e inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual std::string </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a5162368a30a0fc10d69359665b5d8e0e">serialise</a> () const</td></tr>
<tr class="memdesc:a5162368a30a0fc10d69359665b5d8e0e inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Return this object's parameters serialised as a single string. <a href="classXapian_1_1Weight.html#a5162368a30a0fc10d69359665b5d8e0e">More...</a><br /></td></tr>
<tr class="separator:a5162368a30a0fc10d69359665b5d8e0e inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a023bfd724c7ee58666710e0d28639e41 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual <a class="el" href="classXapian_1_1Weight.html">Weight</a> * </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a023bfd724c7ee58666710e0d28639e41">unserialise</a> (const std::string &serialised) const</td></tr>
<tr class="memdesc:a023bfd724c7ee58666710e0d28639e41 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Unserialise parameters. <a href="classXapian_1_1Weight.html#a023bfd724c7ee58666710e0d28639e41">More...</a><br /></td></tr>
<tr class="separator:a023bfd724c7ee58666710e0d28639e41 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a6b60672542f4252fd000641a359107a1 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a6b60672542f4252fd000641a359107a1">get_sumpart</a> (<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> wdf, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> doclen, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> uniqterms) const =0</td></tr>
<tr class="memdesc:a6b60672542f4252fd000641a359107a1 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Calculate the weight contribution for this object's term to a document. <a href="classXapian_1_1Weight.html#a6b60672542f4252fd000641a359107a1">More...</a><br /></td></tr>
<tr class="separator:a6b60672542f4252fd000641a359107a1 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a791cd50a4ab7f2c4f1d9786433033d79 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a791cd50a4ab7f2c4f1d9786433033d79">get_maxpart</a> () const =0</td></tr>
<tr class="memdesc:a791cd50a4ab7f2c4f1d9786433033d79 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Return an upper bound on what <a class="el" href="classXapian_1_1Weight.html#a6b60672542f4252fd000641a359107a1" title="Calculate the weight contribution for this object's term to a document.">get_sumpart()</a> can return for any document. <a href="classXapian_1_1Weight.html#a791cd50a4ab7f2c4f1d9786433033d79">More...</a><br /></td></tr>
<tr class="separator:a791cd50a4ab7f2c4f1d9786433033d79 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a77d87bf5be452399b7c9f72f3b41e5c0 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a77d87bf5be452399b7c9f72f3b41e5c0">get_sumextra</a> (<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> doclen, <a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> uniqterms) const =0</td></tr>
<tr class="memdesc:a77d87bf5be452399b7c9f72f3b41e5c0 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Calculate the term-independent weight component for a document. <a href="classXapian_1_1Weight.html#a77d87bf5be452399b7c9f72f3b41e5c0">More...</a><br /></td></tr>
<tr class="separator:a77d87bf5be452399b7c9f72f3b41e5c0 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a019d010275b6e8130a4c5c746fdf32a1 inherit pub_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual double </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a019d010275b6e8130a4c5c746fdf32a1">get_maxextra</a> () const =0</td></tr>
<tr class="memdesc:a019d010275b6e8130a4c5c746fdf32a1 inherit pub_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Return an upper bound on what <a class="el" href="classXapian_1_1Weight.html#a77d87bf5be452399b7c9f72f3b41e5c0" title="Calculate the term-independent weight component for a document.">get_sumextra()</a> can return for any document. <a href="classXapian_1_1Weight.html#a019d010275b6e8130a4c5c746fdf32a1">More...</a><br /></td></tr>
<tr class="separator:a019d010275b6e8130a4c5c746fdf32a1 inherit pub_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
</table><table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="inherited" name="inherited"></a>
Additional Inherited Members</h2></td></tr>
<tr class="inherit_header pub_types_classXapian_1_1Weight"><td colspan="2" onclick="javascript:toggleInherit('pub_types_classXapian_1_1Weight')"><img src="closed.png" alt="-"/> Public Types inherited from <a class="el" href="classXapian_1_1Weight.html">Xapian::Weight</a></td></tr>
<tr class="memitem:a3181bb7619bd560a3a2c21ece3213ce0 inherit pub_types_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">enum  </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a3181bb7619bd560a3a2c21ece3213ce0">type_smoothing</a> { <br />
  <b>TWO_STAGE_SMOOTHING</b> = 1
, <b>DIRICHLET_SMOOTHING</b> = 2
, <b>ABSOLUTE_DISCOUNT_SMOOTHING</b> = 3
, <b>JELINEK_MERCER_SMOOTHING</b> = 4
, <br />
  <b>DIRICHLET_PLUS_SMOOTHING</b> = 5
<br />
}</td></tr>
<tr class="memdesc:a3181bb7619bd560a3a2c21ece3213ce0"><td class="mdescLeft"> </td><td class="mdescRight">Type of smoothing to use with the Language Model Weighting scheme. <a href="classXapian_1_1Weight.html#a3181bb7619bd560a3a2c21ece3213ce0">More...</a><br /></td></tr>
<tr class="separator:a3181bb7619bd560a3a2c21ece3213ce0 inherit pub_types_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="inherit_header pro_types_classXapian_1_1Weight"><td colspan="2" onclick="javascript:toggleInherit('pro_types_classXapian_1_1Weight')"><img src="closed.png" alt="-"/> Protected Types inherited from <a class="el" href="classXapian_1_1Weight.html">Xapian::Weight</a></td></tr>
<tr class="memitem:ae3c11f1d2d96a18e0eb9b9b31c5c5479 inherit pro_types_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">enum  </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479">stat_flags</a> { <br />
  <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479abce4fe48f6f680644bd352acc937856e">COLLECTION_SIZE</a> = 1
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a632727fa617eec2dfa9ad19e6adcb926">RSET_SIZE</a> = 2
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a5ce8ff7822abec06e0f5ac956d7b247e">AVERAGE_LENGTH</a> = 4
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479ab2b087be2c0ffd8a2ea214298156f99b">TERMFREQ</a> = 8
, <br />
  <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479afd0979b74a0cf07991edc4af31ed55be">RELTERMFREQ</a> = 16
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a1a95530f6aa2ca909e4c1620aed8192b">QUERY_LENGTH</a> = 32
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479ab383711f122cf1927e418dc94e8ed1a7">WQF</a> = 64
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479afe84a106f8ec14c79acdfc29d9378aa2">WDF</a> = 128
, <br />
  <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a92ac55fbe32f39c3b4cdcab135ac0722">DOC_LENGTH</a> = 256
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479ac9f88f7ca707347bcce2c1ad0abdf531">DOC_LENGTH_MIN</a> = 512
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a8f07b317ab1fca84d17cab78aa412e37">DOC_LENGTH_MAX</a> = 1024
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479abe608cc5dc83deef0f35c13a69aa15dc">WDF_MAX</a> = 2048
, <br />
  <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479ad923b48160007ce82f9db96f4f44c700">COLLECTION_FREQ</a> = 4096
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a429d945066f46ee1449e1be35f897bf2">UNIQUE_TERMS</a> = 8192
, <a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479a5c50665a837865406b7aff847d0a07d7">TOTAL_LENGTH</a> = COLLECTION_SIZE | AVERAGE_LENGTH
<br />
}</td></tr>
<tr class="memdesc:ae3c11f1d2d96a18e0eb9b9b31c5c5479"><td class="mdescLeft"> </td><td class="mdescRight">Stats which the weighting scheme can use (see <em><a class="el" href="classXapian_1_1Weight.html#a77b1424d5f5a5b2d4848175979da6475" title="Tell Xapian that your subclass will want a particular statistic.">need_stat()</a></em>). <a href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479">More...</a><br /></td></tr>
<tr class="separator:ae3c11f1d2d96a18e0eb9b9b31c5c5479 inherit pro_types_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="inherit_header pro_methods_classXapian_1_1Weight"><td colspan="2" onclick="javascript:toggleInherit('pro_methods_classXapian_1_1Weight')"><img src="closed.png" alt="-"/> Protected Member Functions inherited from <a class="el" href="classXapian_1_1Weight.html">Xapian::Weight</a></td></tr>
<tr class="memitem:a77b1424d5f5a5b2d4848175979da6475 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a77b1424d5f5a5b2d4848175979da6475">need_stat</a> (<a class="el" href="classXapian_1_1Weight.html#ae3c11f1d2d96a18e0eb9b9b31c5c5479">stat_flags</a> flag)</td></tr>
<tr class="memdesc:a77b1424d5f5a5b2d4848175979da6475 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Tell <a class="el" href="namespaceXapian.html" title="The Xapian namespace contains public interfaces for the Xapian library.">Xapian</a> that your subclass will want a particular statistic. <a href="classXapian_1_1Weight.html#a77b1424d5f5a5b2d4848175979da6475">More...</a><br /></td></tr>
<tr class="separator:a77b1424d5f5a5b2d4848175979da6475 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a71cd77c24183e837313ec13d967ddf2c inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top">virtual void </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a71cd77c24183e837313ec13d967ddf2c">init</a> (double factor)=0</td></tr>
<tr class="memdesc:a71cd77c24183e837313ec13d967ddf2c inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Allow the subclass to perform any initialisation it needs to. <a href="classXapian_1_1Weight.html#a71cd77c24183e837313ec13d967ddf2c">More...</a><br /></td></tr>
<tr class="separator:a71cd77c24183e837313ec13d967ddf2c inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aa7acc105949dcb3b8b343a598dd01487 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#aa7acc105949dcb3b8b343a598dd01487">Weight</a> (const <a class="el" href="classXapian_1_1Weight.html">Weight</a> &)</td></tr>
<tr class="memdesc:aa7acc105949dcb3b8b343a598dd01487 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Don't allow copying. <a href="classXapian_1_1Weight.html#aa7acc105949dcb3b8b343a598dd01487">More...</a><br /></td></tr>
<tr class="separator:aa7acc105949dcb3b8b343a598dd01487 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aa0c27dd474ebbf95c8b3247c2a49686f inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="aa0c27dd474ebbf95c8b3247c2a49686f" name="aa0c27dd474ebbf95c8b3247c2a49686f"></a>
<a class="el" href="namespaceXapian.html#a9bbd62a8e56ea4619e4e59afb32aced6">Xapian::doccount</a> </td><td class="memItemRight" valign="bottom"><b>get_collection_size</b> () const</td></tr>
<tr class="memdesc:aa0c27dd474ebbf95c8b3247c2a49686f inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The number of documents in the collection. <br /></td></tr>
<tr class="separator:aa0c27dd474ebbf95c8b3247c2a49686f inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a7d32c6eb63d262e27c8e06b6254dc2ae inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a7d32c6eb63d262e27c8e06b6254dc2ae" name="a7d32c6eb63d262e27c8e06b6254dc2ae"></a>
<a class="el" href="namespaceXapian.html#a9bbd62a8e56ea4619e4e59afb32aced6">Xapian::doccount</a> </td><td class="memItemRight" valign="bottom"><b>get_rset_size</b> () const</td></tr>
<tr class="memdesc:a7d32c6eb63d262e27c8e06b6254dc2ae inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The number of documents marked as relevant. <br /></td></tr>
<tr class="separator:a7d32c6eb63d262e27c8e06b6254dc2ae inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aac08743bb731357a46f58bc1c9dd8739 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="aac08743bb731357a46f58bc1c9dd8739" name="aac08743bb731357a46f58bc1c9dd8739"></a>
<a class="el" href="namespaceXapian.html#a63b13d3a36fcab9975658e32643d86b5">Xapian::doclength</a> </td><td class="memItemRight" valign="bottom"><b>get_average_length</b> () const</td></tr>
<tr class="memdesc:aac08743bb731357a46f58bc1c9dd8739 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The average length of a document in the collection. <br /></td></tr>
<tr class="separator:aac08743bb731357a46f58bc1c9dd8739 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a4e8361381e8111e5c0936bef91637d20 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a4e8361381e8111e5c0936bef91637d20" name="a4e8361381e8111e5c0936bef91637d20"></a>
<a class="el" href="namespaceXapian.html#a9bbd62a8e56ea4619e4e59afb32aced6">Xapian::doccount</a> </td><td class="memItemRight" valign="bottom"><b>get_termfreq</b> () const</td></tr>
<tr class="memdesc:a4e8361381e8111e5c0936bef91637d20 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The number of documents which this term indexes. <br /></td></tr>
<tr class="separator:a4e8361381e8111e5c0936bef91637d20 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a31d2eb808f1d13419c5148b334cdb702 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a31d2eb808f1d13419c5148b334cdb702" name="a31d2eb808f1d13419c5148b334cdb702"></a>
<a class="el" href="namespaceXapian.html#a9bbd62a8e56ea4619e4e59afb32aced6">Xapian::doccount</a> </td><td class="memItemRight" valign="bottom"><b>get_reltermfreq</b> () const</td></tr>
<tr class="memdesc:a31d2eb808f1d13419c5148b334cdb702 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The number of relevant documents which this term indexes. <br /></td></tr>
<tr class="separator:a31d2eb808f1d13419c5148b334cdb702 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a8b889fbca34923d6077b3d8e39d08cc9 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a8b889fbca34923d6077b3d8e39d08cc9" name="a8b889fbca34923d6077b3d8e39d08cc9"></a>
<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><b>get_collection_freq</b> () const</td></tr>
<tr class="memdesc:a8b889fbca34923d6077b3d8e39d08cc9 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The collection frequency of the term. <br /></td></tr>
<tr class="separator:a8b889fbca34923d6077b3d8e39d08cc9 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a0b1a15b14be112f56d1fea7557b39484 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a0b1a15b14be112f56d1fea7557b39484" name="a0b1a15b14be112f56d1fea7557b39484"></a>
<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><b>get_query_length</b> () const</td></tr>
<tr class="memdesc:a0b1a15b14be112f56d1fea7557b39484 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The length of the query. <br /></td></tr>
<tr class="separator:a0b1a15b14be112f56d1fea7557b39484 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a88dd563e37f13c30075159ad58682f88 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a88dd563e37f13c30075159ad58682f88" name="a88dd563e37f13c30075159ad58682f88"></a>
<a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><b>get_wqf</b> () const</td></tr>
<tr class="memdesc:a88dd563e37f13c30075159ad58682f88 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">The within-query-frequency of this term. <br /></td></tr>
<tr class="separator:a88dd563e37f13c30075159ad58682f88 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ad26c71f5932cf020463a6566df03baa9 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#ad26c71f5932cf020463a6566df03baa9">get_doclength_upper_bound</a> () const</td></tr>
<tr class="memdesc:ad26c71f5932cf020463a6566df03baa9 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">An upper bound on the maximum length of any document in the database. <a href="classXapian_1_1Weight.html#ad26c71f5932cf020463a6566df03baa9">More...</a><br /></td></tr>
<tr class="separator:ad26c71f5932cf020463a6566df03baa9 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a206b260ee9e90ebc5cc8de6f8fd6e2c5 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#a206b260ee9e90ebc5cc8de6f8fd6e2c5">get_doclength_lower_bound</a> () const</td></tr>
<tr class="memdesc:a206b260ee9e90ebc5cc8de6f8fd6e2c5 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">A lower bound on the minimum length of any document in the database. <a href="classXapian_1_1Weight.html#a206b260ee9e90ebc5cc8de6f8fd6e2c5">More...</a><br /></td></tr>
<tr class="separator:a206b260ee9e90ebc5cc8de6f8fd6e2c5 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aff00a44dc04eae5864de75f319889433 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classXapian_1_1Weight.html#aff00a44dc04eae5864de75f319889433">get_wdf_upper_bound</a> () const</td></tr>
<tr class="memdesc:aff00a44dc04eae5864de75f319889433 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">An upper bound on the wdf of this term. <a href="classXapian_1_1Weight.html#aff00a44dc04eae5864de75f319889433">More...</a><br /></td></tr>
<tr class="separator:aff00a44dc04eae5864de75f319889433 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a5e532ba58b2617e23f440a4a168a67a9 inherit pro_methods_classXapian_1_1Weight"><td class="memItemLeft" align="right" valign="top"><a id="a5e532ba58b2617e23f440a4a168a67a9" name="a5e532ba58b2617e23f440a4a168a67a9"></a>
<a class="el" href="namespaceXapian.html#ae3e1d1dd5c1307181b0bad1a689a5872">Xapian::totallength</a> </td><td class="memItemRight" valign="bottom"><b>get_total_length</b> () const</td></tr>
<tr class="memdesc:a5e532ba58b2617e23f440a4a168a67a9 inherit pro_methods_classXapian_1_1Weight"><td class="mdescLeft"> </td><td class="mdescRight">Total length of all documents in the collection. <br /></td></tr>
<tr class="separator:a5e532ba58b2617e23f440a4a168a67a9 inherit pro_methods_classXapian_1_1Weight"><td class="memSeparator" colspan="2"> </td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p ><a class="el" href="classXapian_1_1Weight.html" title="Abstract base class for weighting schemes.">Xapian::Weight</a> subclass implementing the BM25+ probabilistic formula. </p>
</div><h2 class="groupheader">Constructor & Destructor Documentation</h2>
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<h2 class="memtitle"><span class="permalink"><a href="#ae42d928ab5f029167d227eefaaa7bc88">◆ </a></span>BM25PlusWeight()</h2>
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<td class="memname">Xapian::BM25PlusWeight::BM25PlusWeight </td>
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<td class="paramtype">double </td>
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<p>Construct a <a class="el" href="classXapian_1_1BM25PlusWeight.html" title="Xapian::Weight subclass implementing the BM25+ probabilistic formula.">BM25PlusWeight</a>. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">k1</td><td>A non-negative parameter controlling how influential within-document-frequency (wdf) is. k1=0 means that wdf doesn't affect the weights. The larger k1 is, the more wdf influences the weights. (default 1)</td></tr>
<tr><td class="paramname">k2</td><td>A non-negative parameter which controls the strength of a correction factor which depends upon query length and normalised document length. k2=0 disable this factor; larger k2 makes it stronger. The paper which describes BM25+ ignores BM25's document-independent component (so implicitly k2=0), but we support non-zero k2 too. (default 0)</td></tr>
<tr><td class="paramname">k3</td><td>A non-negative parameter controlling how influential within-query-frequency (wqf) is. k3=0 means that wqf doesn't affect the weights. The larger k3 is, the more wqf influences the weights. (default 1)</td></tr>
<tr><td class="paramname">b</td><td>A parameter between 0 and 1, controlling how strong the document length normalisation of wdf is. 0 means no normalisation; 1 means full normalisation. (default 0.5)</td></tr>
<tr><td class="paramname">min_normlen</td><td>A parameter specifying a minimum value for normalised document length. Normalised document length values less than this will be clamped to this value, helping to prevent very short documents getting large weights. (default 0.5)</td></tr>
<tr><td class="paramname">delta</td><td>A parameter for pseudo tf value to control the scale of the tf lower bound. Delta(δ) can be tuned for example from 0.0 to 1.5 but BM25+ can still work effectively across collections with a fixed δ = 1.0. (default 1.0) </td></tr>
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<h2 class="groupheader">Member Function Documentation</h2>
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<h2 class="memtitle"><span class="permalink"><a href="#ab326326a2a50cc91e066ad83cdf507eb">◆ </a></span>get_maxextra()</h2>
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<p>Return an upper bound on what <a class="el" href="classXapian_1_1BM25PlusWeight.html#a61ead2c8f139895fc69c10f2c9952e59" title="Calculate the term-independent weight component for a document.">get_sumextra()</a> can return for any document. </p>
<p >This information is used by the matcher to perform various optimisations, so strive to make the bound as tight as possible. </p>
<p>Implements <a class="el" href="classXapian_1_1Weight.html#a019d010275b6e8130a4c5c746fdf32a1">Xapian::Weight</a>.</p>
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<h2 class="memtitle"><span class="permalink"><a href="#aa31188c0036ccaf9a0c00556a8dfb8bb">◆ </a></span>get_maxpart()</h2>
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<td class="memname">double Xapian::BM25PlusWeight::get_maxpart </td>
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<p>Return an upper bound on what <a class="el" href="classXapian_1_1BM25PlusWeight.html#aa38b5f0fc4dbf45eb876ca3552dc7871" title="Calculate the weight contribution for this object's term to a document.">get_sumpart()</a> can return for any document. </p>
<p >This information is used by the matcher to perform various optimisations, so strive to make the bound as tight as possible. </p>
<p>Implements <a class="el" href="classXapian_1_1Weight.html#a791cd50a4ab7f2c4f1d9786433033d79">Xapian::Weight</a>.</p>
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<h2 class="memtitle"><span class="permalink"><a href="#a61ead2c8f139895fc69c10f2c9952e59">◆ </a></span>get_sumextra()</h2>
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<td class="memname">double Xapian::BM25PlusWeight::get_sumextra </td>
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<p>Calculate the term-independent weight component for a document. </p>
<p >The parameter gives information about the document which may be used in the calculations:</p>
<dl class="params"><dt>Parameters</dt><dd>
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<tr><td class="paramname">doclen</td><td>The document's length (unnormalised). </td></tr>
<tr><td class="paramname">uniqterms</td><td>The number of unique terms in the document. </td></tr>
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<p>Implements <a class="el" href="classXapian_1_1Weight.html#a77d87bf5be452399b7c9f72f3b41e5c0">Xapian::Weight</a>.</p>
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<td class="paramtype"><a class="el" href="namespaceXapian.html#a4464380f6fa0055b5f26b8d03ae170e2">Xapian::termcount</a> </td>
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<p>Calculate the weight contribution for this object's term to a document. </p>
<p >The parameters give information about the document which may be used in the calculations:</p>
<dl class="params"><dt>Parameters</dt><dd>
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<tr><td class="paramname">wdf</td><td>The within document frequency of the term in the document. </td></tr>
<tr><td class="paramname">doclen</td><td>The document's length (unnormalised). </td></tr>
<tr><td class="paramname">uniqterms</td><td>Number of unique terms in the document (used for absolute smoothing). </td></tr>
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<p>Implements <a class="el" href="classXapian_1_1Weight.html#a6b60672542f4252fd000641a359107a1">Xapian::Weight</a>.</p>
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<h2 class="memtitle"><span class="permalink"><a href="#a456922fa3c01a6dcdca7c2d283786141">◆ </a></span>name()</h2>
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<p>Return the name of this weighting scheme. </p>
<p >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.</p>
<p >Return the full namespace-qualified name of your class here - if your class is called FooWeight, return "FooWeight" from this method (<a class="el" href="classXapian_1_1BM25Weight.html" title="Xapian::Weight subclass implementing the BM25 probabilistic formula.">Xapian::BM25Weight</a> returns "Xapian::BM25Weight" here).</p>
<p >If you don't want to support the remote backend, you can use the default implementation which simply returns an empty string. </p>
<p>Reimplemented from <a class="el" href="classXapian_1_1Weight.html#a6106970d1a1e9600c9b32cc6ec96bf6b">Xapian::Weight</a>.</p>
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<h2 class="memtitle"><span class="permalink"><a href="#a637b5ea25f921f36dfb8b36aafb407b4">◆ </a></span>serialise()</h2>
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<p>Return this object's parameters serialised as a single string. </p>
<p >If you don't want to support the remote backend, you can use the default implementation which simply throws <a class="el" href="classXapian_1_1UnimplementedError.html" title="UnimplementedError indicates an attempt to use an unimplemented feature.">Xapian::UnimplementedError</a>. </p>
<p>Reimplemented from <a class="el" href="classXapian_1_1Weight.html#a5162368a30a0fc10d69359665b5d8e0e">Xapian::Weight</a>.</p>
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<h2 class="memtitle"><span class="permalink"><a href="#a9d1e21b49c34b415e40b30c9bf3435b1">◆ </a></span>unserialise()</h2>
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<td class="memname"><a class="el" href="classXapian_1_1BM25PlusWeight.html">BM25PlusWeight</a> * Xapian::BM25PlusWeight::unserialise </td>
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<p>Unserialise parameters. </p>
<p >This method unserialises parameters serialised by the <em><a class="el" href="classXapian_1_1BM25PlusWeight.html#a637b5ea25f921f36dfb8b36aafb407b4" title="Return this object's parameters serialised as a single string.">serialise()</a></em> method and allocates and returns a new object initialised with them.</p>
<p >If you don't want to support the remote backend, you can use the default implementation which simply throws <a class="el" href="classXapian_1_1UnimplementedError.html" title="UnimplementedError indicates an attempt to use an unimplemented feature.">Xapian::UnimplementedError</a>.</p>
<p >Note that the returned object will be deallocated by <a class="el" href="namespaceXapian.html" title="The Xapian namespace contains public interfaces for the Xapian library.">Xapian</a> after use with "delete". If you want to handle the deletion in a special way (for example when wrapping the <a class="el" href="namespaceXapian.html" title="The Xapian namespace contains public interfaces for the Xapian library.">Xapian</a> API for use from another language) then you can define a static <code>operator delete</code> method in your subclass as shown here: <a href="https://trac.xapian.org/ticket/554#comment:1">https://trac.xapian.org/ticket/554#comment:1</a></p>
<dl class="params"><dt>Parameters</dt><dd>
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<tr><td class="paramname">serialised</td><td>A string containing the serialised parameters. </td></tr>
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<p>Reimplemented from <a class="el" href="classXapian_1_1Weight.html#a023bfd724c7ee58666710e0d28639e41">Xapian::Weight</a>.</p>
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<hr/>The documentation for this class was generated from the following file:<ul>
<li>xapian/<a class="el" href="weight_8h.html">weight.h</a></li>
</ul>
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