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  26. <div class="titlepage"><div><div><h3 class="title">
  27. <a name="boost_multiprecision.ref.mpf_ref"></a><a class="link" href="mpf_ref.html" title="gmp_float">gmp_float</a>
  28. </h3></div></div></div>
  29. <pre class="programlisting"><span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">{</span> <span class="keyword">namespace</span> <span class="identifier">multiprecision</span><span class="special">{</span>
  30. <span class="keyword">template</span> <span class="special">&lt;</span><span class="keyword">unsigned</span> <span class="identifier">Digits10</span><span class="special">&gt;</span>
  31. <span class="keyword">class</span> <span class="identifier">gmp_float</span><span class="special">;</span>
  32. <span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">gmp_float</span><span class="special">&lt;</span><span class="number">50</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">mpf_float_50</span><span class="special">;</span>
  33. <span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">gmp_float</span><span class="special">&lt;</span><span class="number">100</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">mpf_float_100</span><span class="special">;</span>
  34. <span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">gmp_float</span><span class="special">&lt;</span><span class="number">500</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">mpf_float_500</span><span class="special">;</span>
  35. <span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">gmp_float</span><span class="special">&lt;</span><span class="number">1000</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">mpf_float_1000</span><span class="special">;</span>
  36. <span class="keyword">typedef</span> <span class="identifier">number</span><span class="special">&lt;</span><span class="identifier">gmp_float</span><span class="special">&lt;</span><span class="number">0</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">mpf_float</span><span class="special">;</span>
  37. <span class="special">}}</span> <span class="comment">// namespaces</span>
  38. </pre>
  39. <p>
  40. Class template <code class="computeroutput"><span class="identifier">gmp_float</span></code>
  41. fulfils all of the requirements for a <a class="link" href="backendconc.html" title="Backend Requirements">Backend</a>
  42. type. Its members and non-member functions are deliberately not documented:
  43. these are considered implementation details that are subject to change.
  44. </p>
  45. <p>
  46. The class takes a single template parameter - <code class="computeroutput"><span class="identifier">Digits10</span></code>
  47. - which is the number of decimal digits precision the type should support.
  48. When this parameter is zero, then the precision can be set at runtime via
  49. <code class="computeroutput"><span class="identifier">number</span><span class="special">::</span><span class="identifier">default_precision</span></code> and <code class="computeroutput"><span class="identifier">number</span><span class="special">::</span><span class="identifier">precision</span></code>.
  50. Note that this type does not in any way change the GMP library's global state
  51. (for example it does not change the default precision of the mpf_t data type),
  52. therefore you can safely mix this type with existing code that uses GMP,
  53. and also mix <code class="computeroutput"><span class="identifier">gmp_float</span></code>s of
  54. differing precision.
  55. </p>
  56. <p>
  57. The type of <code class="computeroutput"><span class="identifier">number_category</span><span class="special">&lt;</span><span class="identifier">cpp_int</span><span class="special">&lt;</span><span class="identifier">Args</span><span class="special">...&gt;</span> <span class="special">&gt;::</span><span class="identifier">type</span></code> is <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">int_</span><span class="special">&lt;</span><span class="identifier">number_kind_floating_point</span><span class="special">&gt;</span></code>.
  58. </p>
  59. <p>
  60. More information on this type can be found in the <a class="link" href="../tut/floats/gmp_float.html" title="gmp_float">tutorial</a>.
  61. </p>
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  64. <td align="left"></td>
  65. <td align="right"><div class="copyright-footer">Copyright &#169; 2002-2019 John Maddock
  66. and Christopher Kormanyos<p>
  67. Distributed under the Boost Software License, Version 1.0. (See accompanying
  68. file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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