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| <h4 class="subsection">20.8.4 Remainder Functions</h4> |
| |
| <p>The functions in this section compute the remainder on division of two |
| floating-point numbers. Each is a little different; pick the one that |
| suits your problem. |
| |
| <!-- math.h --> |
| <!-- ISO --> |
| <div class="defun"> |
| — Function: double <b>fmod</b> (<var>double numerator, double denominator</var>)<var><a name="index-fmod-2472"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- ISO --> |
| — Function: float <b>fmodf</b> (<var>float numerator, float denominator</var>)<var><a name="index-fmodf-2473"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- ISO --> |
| — Function: long double <b>fmodl</b> (<var>long double numerator, long double denominator</var>)<var><a name="index-fmodl-2474"></a></var><br> |
| <blockquote><p>These functions compute the remainder from the division of |
| <var>numerator</var> by <var>denominator</var>. Specifically, the return value is |
| <var>numerator</var><code> - </code><var>n</var><code> * </code><var>denominator</var><code><!-- /@w --></code>, where <var>n</var> |
| is the quotient of <var>numerator</var> divided by <var>denominator</var>, rounded |
| towards zero to an integer. Thus, <code>fmod (6.5, 2.3)</code><!-- /@w --> returns |
| <code>1.9</code>, which is <code>6.5</code> minus <code>4.6</code>. |
| |
| <p>The result has the same sign as the <var>numerator</var> and has magnitude |
| less than the magnitude of the <var>denominator</var>. |
| |
| <p>If <var>denominator</var> is zero, <code>fmod</code> signals a domain error. |
| </p></blockquote></div> |
| |
| <!-- math.h --> |
| <!-- BSD --> |
| <div class="defun"> |
| — Function: double <b>drem</b> (<var>double numerator, double denominator</var>)<var><a name="index-drem-2475"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- BSD --> |
| — Function: float <b>dremf</b> (<var>float numerator, float denominator</var>)<var><a name="index-dremf-2476"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- BSD --> |
| — Function: long double <b>dreml</b> (<var>long double numerator, long double denominator</var>)<var><a name="index-dreml-2477"></a></var><br> |
| <blockquote><p>These functions are like <code>fmod</code> except that they round the |
| internal quotient <var>n</var> to the nearest integer instead of towards zero |
| to an integer. For example, <code>drem (6.5, 2.3)</code> returns <code>-0.4</code>, |
| which is <code>6.5</code> minus <code>6.9</code>. |
| |
| <p>The absolute value of the result is less than or equal to half the |
| absolute value of the <var>denominator</var>. The difference between |
| <code>fmod (</code><var>numerator</var><code>, </code><var>denominator</var><code>)</code> and <code>drem |
| (</code><var>numerator</var><code>, </code><var>denominator</var><code>)</code> is always either |
| <var>denominator</var>, minus <var>denominator</var>, or zero. |
| |
| <p>If <var>denominator</var> is zero, <code>drem</code> signals a domain error. |
| </p></blockquote></div> |
| |
| <!-- math.h --> |
| <!-- BSD --> |
| <div class="defun"> |
| — Function: double <b>remainder</b> (<var>double numerator, double denominator</var>)<var><a name="index-remainder-2478"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- BSD --> |
| — Function: float <b>remainderf</b> (<var>float numerator, float denominator</var>)<var><a name="index-remainderf-2479"></a></var><br> |
| <blockquote><!-- math.h --> |
| <!-- BSD --> |
| — Function: long double <b>remainderl</b> (<var>long double numerator, long double denominator</var>)<var><a name="index-remainderl-2480"></a></var><br> |
| <blockquote><p>This function is another name for <code>drem</code>. |
| </p></blockquote></div> |
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