選択できるのは25トピックまでです。 トピックは、先頭が英数字で、英数字とダッシュ('-')を使用した35文字以内のものにしてください。

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  53. <a name="trunc_002c-truncf_002d_002d_002dround-to-integer_002c-towards-zero"></a>
  54. <h3 class="section">1.58 <code>trunc</code>, <code>truncf</code>&mdash;round to integer, towards zero</h3>
  55. <a name="index-trunc"></a>
  56. <a name="index-truncf"></a>
  57. <p><strong>Synopsis</strong>
  58. </p><div class="example">
  59. <pre class="example">#include &lt;math.h&gt;
  60. double trunc(double <var>x</var>);
  61. float truncf(float <var>x</var>);
  62. </pre></div>
  63. <p><strong>Description</strong><br>
  64. The <code>trunc</code> functions round their argument to the integer value, in
  65. floating format, nearest to but no larger in magnitude than the
  66. argument, regardless of the current rounding direction. (While the
  67. &quot;inexact&quot; floating-point exception behavior is unspecified by the C
  68. standard, the <code>trunc</code> functions are written so that &quot;inexact&quot; is not
  69. raised if the result does not equal the argument, which behavior is as
  70. recommended by IEEE 754 for its related functions.)
  71. </p>
  72. <br>
  73. <p><strong>Returns</strong><br>
  74. <var>x</var> truncated to an integral value.
  75. </p>
  76. <br>
  77. <p><strong>Portability</strong><br>
  78. ANSI C, POSIX
  79. </p>
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