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<li><a class="el" href="classgeos_1_1precision_1_1CommonBits.html">geos::precision::CommonBits</a> </li>
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<a href="#pub-methods">Public Member Functions</a> |
<a href="#pub-static-methods">Static Public Member Functions</a> </div>
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<h1>geos::precision::CommonBits Class Reference</h1> </div>
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<p>Determines the maximum number of common most-significant bits in the mantissa of one or numbers.
<a href="#_details">More...</a></p>
<p><code>#include <<a class="el" href="CommonBits_8h_source.html">CommonBits.h</a>></code></p>
<p><a href="classgeos_1_1precision_1_1CommonBits-members.html">List of all members.</a></p>
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<tr><td colspan="2"><h2><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="ae35c2c9b6b224394eba7857660150cf2"></a><!-- doxytag: member="geos::precision::CommonBits::add" ref="ae35c2c9b6b224394eba7857660150cf2" args="(double num)" -->
void </td><td class="memItemRight" valign="bottom"><b>add</b> (double num)</td></tr>
<tr><td class="memItemLeft" align="right" valign="top"><a class="anchor" id="ad534127f8b773d447407755626875b12"></a><!-- doxytag: member="geos::precision::CommonBits::getCommon" ref="ad534127f8b773d447407755626875b12" args="()" -->
double </td><td class="memItemRight" valign="bottom"><b>getCommon</b> ()</td></tr>
<tr><td colspan="2"><h2><a name="pub-static-methods"></a>
Static Public Member Functions</h2></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static int64 </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1precision_1_1CommonBits.html#acd2915c5248f5c5212f8bb6f0c392bcd">signExpBits</a> (int64 num)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Computes the bit pattern for the sign and exponent of a double-precision number. <a href="#acd2915c5248f5c5212f8bb6f0c392bcd"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static int </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1precision_1_1CommonBits.html#a0d84e408acf9c7999315d528e8a5c7fe">numCommonMostSigMantissaBits</a> (int64 num1, int64 num2)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">This computes the number of common most-significant bits in the mantissas of two double-precision numbers. <a href="#a0d84e408acf9c7999315d528e8a5c7fe"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static int64 </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1precision_1_1CommonBits.html#a34fdd6bccb7d15b1d39650c23c289cdb">zeroLowerBits</a> (int64 bits, int nBits)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Zeroes the lower n bits of a bitstring. <a href="#a34fdd6bccb7d15b1d39650c23c289cdb"></a><br/></td></tr>
<tr><td class="memItemLeft" align="right" valign="top">static int </td><td class="memItemRight" valign="bottom"><a class="el" href="classgeos_1_1precision_1_1CommonBits.html#a2dd5813222adb4f5feaeff3e2b9aac6d">getBit</a> (int64 bits, int i)</td></tr>
<tr><td class="mdescLeft"> </td><td class="mdescRight">Extracts the i'th bit of a bitstring. <a href="#a2dd5813222adb4f5feaeff3e2b9aac6d"></a><br/></td></tr>
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<hr/><a name="_details"></a><h2>Detailed Description</h2>
<p>Determines the maximum number of common most-significant bits in the mantissa of one or numbers. </p>
<p>Can be used to compute the double-precision number which is represented by the common bits. If there are no common bits, the number computed is 0.0. </p>
<hr/><h2>Member Function Documentation</h2>
<a class="anchor" id="a2dd5813222adb4f5feaeff3e2b9aac6d"></a><!-- doxytag: member="geos::precision::CommonBits::getBit" ref="a2dd5813222adb4f5feaeff3e2b9aac6d" args="(int64 bits, int i)" -->
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<td class="memname">static int geos::precision::CommonBits::getBit </td>
<td>(</td>
<td class="paramtype">int64 </td>
<td class="paramname"> <em>bits</em>, </td>
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<td></td>
<td class="paramtype">int </td>
<td class="paramname"> <em>i</em></td><td> </td>
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<td>)</td>
<td></td><td></td><td><code> [static]</code></td>
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<p>Extracts the i'th bit of a bitstring. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>bits</em> </td><td>the bitstring to extract from </td></tr>
<tr><td valign="top"></td><td valign="top"><em>i</em> </td><td>the bit to extract </td></tr>
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</dd>
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<dl class="return"><dt><b>Returns:</b></dt><dd>the value of the extracted bit </dd></dl>
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<a class="anchor" id="a0d84e408acf9c7999315d528e8a5c7fe"></a><!-- doxytag: member="geos::precision::CommonBits::numCommonMostSigMantissaBits" ref="a0d84e408acf9c7999315d528e8a5c7fe" args="(int64 num1, int64 num2)" -->
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<td class="memname">static int geos::precision::CommonBits::numCommonMostSigMantissaBits </td>
<td>(</td>
<td class="paramtype">int64 </td>
<td class="paramname"> <em>num1</em>, </td>
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<td class="paramtype">int64 </td>
<td class="paramname"> <em>num2</em></td><td> </td>
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<td></td><td></td><td><code> [static]</code></td>
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<p>This computes the number of common most-significant bits in the mantissas of two double-precision numbers. </p>
<p>It does not count the hidden bit, which is always 1. It does not determine whether the numbers have the same exponent - if they do not, the value computed by this function is meaningless. </p>
<dl><dt><b>Parameters:</b></dt><dd>
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<tr><td valign="top"></td><td valign="top"><em>db</em> </td><td></td></tr>
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<dl class="return"><dt><b>Returns:</b></dt><dd>the number of common most-significant mantissa bits </dd></dl>
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<a class="anchor" id="acd2915c5248f5c5212f8bb6f0c392bcd"></a><!-- doxytag: member="geos::precision::CommonBits::signExpBits" ref="acd2915c5248f5c5212f8bb6f0c392bcd" args="(int64 num)" -->
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<td class="memname">static int64 geos::precision::CommonBits::signExpBits </td>
<td>(</td>
<td class="paramtype">int64 </td>
<td class="paramname"> <em>num</em></td>
<td> ) </td>
<td><code> [static]</code></td>
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<p>Computes the bit pattern for the sign and exponent of a double-precision number. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>num</em> </td><td></td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>the bit pattern for the sign and exponent </dd></dl>
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<a class="anchor" id="a34fdd6bccb7d15b1d39650c23c289cdb"></a><!-- doxytag: member="geos::precision::CommonBits::zeroLowerBits" ref="a34fdd6bccb7d15b1d39650c23c289cdb" args="(int64 bits, int nBits)" -->
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<td class="memname">static int64 geos::precision::CommonBits::zeroLowerBits </td>
<td>(</td>
<td class="paramtype">int64 </td>
<td class="paramname"> <em>bits</em>, </td>
</tr>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">int </td>
<td class="paramname"> <em>nBits</em></td><td> </td>
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<td></td>
<td>)</td>
<td></td><td></td><td><code> [static]</code></td>
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<p>Zeroes the lower n bits of a bitstring. </p>
<dl><dt><b>Parameters:</b></dt><dd>
<table border="0" cellspacing="2" cellpadding="0">
<tr><td valign="top"></td><td valign="top"><em>bits</em> </td><td>the bitstring to alter </td></tr>
<tr><td valign="top"></td><td valign="top"><em>i</em> </td><td>the number of bits to zero </td></tr>
</table>
</dd>
</dl>
<dl class="return"><dt><b>Returns:</b></dt><dd>the zeroed bitstring </dd></dl>
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<hr/>The documentation for this class was generated from the following file:<ul>
<li><a class="el" href="CommonBits_8h_source.html">CommonBits.h</a></li>
</ul>
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