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  26 <div class="titlepage"><div><div><h5 class="title">
  27 <a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_"></a><a name="group__predicates_1ga8772d9d3e5b12b3292f7d94d47310e3e"></a><a class="link" href="nearest_geometry_const____unsigned_.html" title="nearest(Geometry const &amp;, unsigned)">nearest(Geometry
  28           const &amp;, unsigned)</a>
  29 </h5></div></div></div>
  30 <p>
  31             <a class="indexterm" name="idm46186975787280"></a>
  32 Generate <a class="link" href="nearest_geometry_const____unsigned_.html#group__predicates_1ga8772d9d3e5b12b3292f7d94d47310e3e">nearest()</a>
  33             predicate.
  34           </p>
  35 <h6>
  36 <a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.h0"></a>
  37             <span class="phrase"><a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.description"></a></span><a class="link" href="nearest_geometry_const____unsigned_.html#geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.description">Description</a>
  38           </h6>
  39 <p>
  40             When nearest predicate is passed to the query, k-nearest neighbour search
  41             will be performed. <code class="literal"><a class="link" href="nearest_geometry_const____unsigned_.html#group__predicates_1ga8772d9d3e5b12b3292f7d94d47310e3e">nearest()</a></code>
  42             predicate takes a <code class="literal"><code class="computeroutput"><span class="identifier">Geometry</span></code></code>
  43             from which distances to <code class="literal"><code class="computeroutput"><span class="identifier">Values</span></code></code>
  44             are calculated and the maximum number of <code class="literal"><code class="computeroutput"><span class="identifier">Values</span></code></code>
  45             that should be returned. Internally boost::geometry::comparable_distance()
  46             is used to perform the calculation.
  47           </p>
  48 <h6>
  49 <a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.h1"></a>
  50             <span class="phrase"><a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.synopsis"></a></span><a class="link" href="nearest_geometry_const____unsigned_.html#geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.synopsis">Synopsis</a>
  51           </h6>
  52 <pre class="programlisting"><code class="computeroutput"><span class="keyword">template</span><span class="special">&lt;</span></code><code class="computeroutput"><span class="keyword">typename</span> <span class="identifier">Geometry</span></code><code class="computeroutput"><span class="special">&gt;</span></code>
  53 <span class="emphasis"><em>unspecified</em></span> <code class="computeroutput"><span class="identifier">nearest</span></code><code class="computeroutput"><span class="special">(</span></code><code class="computeroutput"><span class="identifier">Geometry</span> <span class="keyword">const</span> <span class="special">&amp;</span></code> <code class="computeroutput"><span class="identifier">geometry</span></code><code class="computeroutput"><span class="special">,</span></code> <code class="computeroutput"><span class="keyword">unsigned</span></code> <code class="computeroutput"><span class="identifier">k</span></code><code class="computeroutput"><span class="special">)</span></code>
  54 </pre>
  55 <h6>
  56 <a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.h2"></a>
  57             <span class="phrase"><a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.parameter_s_"></a></span><a class="link" href="nearest_geometry_const____unsigned_.html#geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.parameter_s_">Parameter(s)</a>
  58           </h6>
  59 <div class="informaltable"><table class="table">
  60 <colgroup>
  61 <col>
  62 <col>
  63 <col>
  64 </colgroup>
  65 <thead><tr>
  66 <th>
  67                     <p>
  68                       Type
  69                     </p>
  70                   </th>
  71 <th>
  72                     <p>
  73                       Name
  74                     </p>
  75                   </th>
  76 <th>
  77                     <p>
  78                       Description
  79                     </p>
  80                   </th>
  81 </tr></thead>
  82 <tbody>
  83 <tr>
  84 <td>
  85                     <p>
  86                       <code class="computeroutput"><span class="identifier">Geometry</span> <span class="keyword">const</span>
  87                       <span class="special">&amp;</span></code>
  88                     </p>
  89                   </td>
  90 <td>
  91                     <p>
  92                       <code class="computeroutput"><span class="identifier">geometry</span></code>
  93                     </p>
  94                   </td>
  95 <td>
  96                     <p>
  97                       The geometry from which distance is calculated.
  98                     </p>
  99                   </td>
 100 </tr>
 101 <tr>
 102 <td>
 103                     <p>
 104                       <code class="computeroutput"><span class="keyword">unsigned</span></code>
 105                     </p>
 106                   </td>
 107 <td>
 108                     <p>
 109                       <code class="computeroutput"><span class="identifier">k</span></code>
 110                     </p>
 111                   </td>
 112 <td>
 113                     <p>
 114                       The maximum number of values to return.
 115                     </p>
 116                   </td>
 117 </tr>
 118 </tbody>
 119 </table></div>
 120 <h6>
 121 <a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.h3"></a>
 122             <span class="phrase"><a name="geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.example"></a></span><a class="link" href="nearest_geometry_const____unsigned_.html#geometry.reference.spatial_indexes.group__predicates.nearest_geometry_const____unsigned_.example">Example</a>
 123           </h6>
 124 <p>
 125 </p>
 126 <pre class="programlisting"><span class="identifier">bgi</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">spatial_index</span><span class="special">,</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="number">5</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span>
 127 <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">spatial_index</span><span class="special">,</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">pt</span><span class="special">,</span> <span class="number">5</span><span class="special">)</span> <span class="special">&amp;&amp;</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">intersects</span><span class="special">(</span><span class="identifier">box</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span>
 128 <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">query</span><span class="special">(</span><span class="identifier">spatial_index</span><span class="special">,</span> <span class="identifier">bgi</span><span class="special">::</span><span class="identifier">nearest</span><span class="special">(</span><span class="identifier">box</span><span class="special">,</span> <span class="number">5</span><span class="special">),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">back_inserter</span><span class="special">(</span><span class="identifier">result</span><span class="special">));</span>
 129 </pre>
 130 <p>
 131           </p>
 132 <div class="warning"><table border="0" summary="Warning">
 133 <tr>
 134 <td rowspan="2" align="center" valign="top" width="25"><img alt="[Warning]" src="../../../../../../../../doc/src/images/warning.png"></td>
 135 <th align="left">Warning</th>
 136 </tr>
 137 <tr><td align="left" valign="top"><p>
 138               Only one <code class="literal"><a class="link" href="nearest_geometry_const____unsigned_.html#group__predicates_1ga8772d9d3e5b12b3292f7d94d47310e3e">nearest()</a></code>
 139               predicate may be used in a query.
 140             </p></td></tr>
 141 </table></div>
 142 </div>
 143 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 144 <td align="left"></td>
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 146       Wulkiewicz, Oracle and/or its affiliates<p>
 147         Distributed under the Boost Software License, Version 1.0. (See accompanying
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