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<a name="remquo_002c-remquof_002d_002d_002dremainder-and-part-of-quotient"></a>
<h3 class="section">1.48 <code>remquo</code>, <code>remquof</code>—remainder and part of quotient</h3>
<a name="index-remquo"></a>
<a name="index-remquof"></a>
<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include <math.h>
double remquo(double <var>x</var>, double <var>y</var>, int *<var>quo</var>);
float remquof(float <var>x</var>, float <var>y</var>, int *<var>quo</var>);
</pre></div>
<p><strong>Description</strong><br>
The <code>remquo</code> functions compute the same remainder as the <code>remainder</code>
functions; this value is in the range -<var>y</var>/2 ... +<var>y</var>/2. In the object
pointed to by <code>quo</code> they store a value whose sign is the sign of <code>x</code>/<code>y</code>
and whose magnitude is congruent modulo 2**n to the magnitude of the integral
quotient of <code>x</code>/<code>y</code>. (That is, <code>quo</code> is given the n lsbs of the
quotient, not counting the sign.) This implementation uses n=31 if int is 32
bits or more, otherwise, n is 1 less than the width of int.
</p>
<p>For example:
</p><div class="smallexample">
<pre class="smallexample"> remquo(-29.0, 3.0, &<var>quo</var>)
</pre></div>
<p>returns -1.0 and sets <var>quo</var>=10, and
</p><div class="smallexample">
<pre class="smallexample"> remquo(-98307.0, 3.0, &<var>quo</var>)
</pre></div>
<p>returns -0.0 and sets <var>quo</var>=-32769, although for 16-bit int, <var>quo</var>=-1. In
the latter case, the actual quotient of -(32769=0x8001) is reduced to -1
because of the 15-bit limitation for the quotient.
</p>
<br>
<p><strong>Returns</strong><br>
When either argument is NaN, NaN is returned. If <var>y</var> is 0 or <var>x</var> is
infinite (and neither is NaN), a domain error occurs (i.e. the "invalid"
floating point exception is raised or errno is set to EDOM), and NaN is
returned.
Otherwise, the <code>remquo</code> functions return <var>x</var> REM <var>y</var>.
</p>
<br>
<p><strong>Bugs</strong><br>
IEEE754-2008 calls for <code>remquo</code>(subnormal, inf) to cause the "underflow"
floating-point exception. This implementation does not.
</p>
<br>
<p><strong>Portability</strong><br>
C99, POSIX.
</p>
<br>
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