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Next: <a href="I_002fO-of-Floats.html#I_002fO-of-Floats" accesskey="n" rel="next">I/O of Floats</a>, Previous: <a href="Float-Arithmetic.html#Float-Arithmetic" accesskey="p" rel="prev">Float Arithmetic</a>, Up: <a href="Floating_002dpoint-Functions.html#Floating_002dpoint-Functions" accesskey="u" rel="up">Floating-point Functions</a> &nbsp; [<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Comparison-Functions-2"></a>
<h3 class="section">7.6 Comparison Functions</h3>
<a name="index-Float-comparison-functions"></a>
<a name="index-Comparison-functions-2"></a>
<dl>
<dt><a name="index-mpf_005fcmp"></a>Function: <em>int</em> <strong>mpf_cmp</strong> <em>(const mpf_t <var>op1</var>, const mpf_t <var>op2</var>)</em></dt>
<dt><a name="index-mpf_005fcmp_005fz"></a>Function: <em>int</em> <strong>mpf_cmp_z</strong> <em>(const mpf_t <var>op1</var>, const mpz_t <var>op2</var>)</em></dt>
<dt><a name="index-mpf_005fcmp_005fd"></a>Function: <em>int</em> <strong>mpf_cmp_d</strong> <em>(const mpf_t <var>op1</var>, double <var>op2</var>)</em></dt>
<dt><a name="index-mpf_005fcmp_005fui"></a>Function: <em>int</em> <strong>mpf_cmp_ui</strong> <em>(const mpf_t <var>op1</var>, unsigned long int <var>op2</var>)</em></dt>
<dt><a name="index-mpf_005fcmp_005fsi"></a>Function: <em>int</em> <strong>mpf_cmp_si</strong> <em>(const mpf_t <var>op1</var>, signed long int <var>op2</var>)</em></dt>
<dd><p>Compare <var>op1</var> and <var>op2</var>. Return a positive value if <em><var>op1</var> &gt;
<var>op2</var></em>, zero if <em><var>op1</var> = <var>op2</var></em>, and a negative value if
<em><var>op1</var> &lt; <var>op2</var></em>.
</p>
<p><code>mpf_cmp_d</code> can be called with an infinity, but results are undefined for
a NaN.
</p></dd></dl>
<dl>
<dt><a name="index-mpf_005feq"></a>Function: <em>int</em> <strong>mpf_eq</strong> <em>(const mpf_t <var>op1</var>, const mpf_t <var>op2</var>, mp_bitcnt_t op3)</em></dt>
<dd><p><strong>This function is mathematically ill-defined and should not be used.</strong>
</p>
<p>Return non-zero if the first <var>op3</var> bits of <var>op1</var> and <var>op2</var> are
equal, zero otherwise. Note that numbers like e.g., 256 (binary 100000000) and
255 (binary 11111111) will never be equal by this function&rsquo;s measure, and
furthermore that 0 will only be equal to itself.
</p></dd></dl>
<dl>
<dt><a name="index-mpf_005freldiff"></a>Function: <em>void</em> <strong>mpf_reldiff</strong> <em>(mpf_t <var>rop</var>, const mpf_t <var>op1</var>, const mpf_t <var>op2</var>)</em></dt>
<dd><p>Compute the relative difference between <var>op1</var> and <var>op2</var> and store the
result in <var>rop</var>. This is <em>abs(<var>op1</var>-<var>op2</var>)/<var>op1</var></em>.
</p></dd></dl>
<dl>
<dt><a name="index-mpf_005fsgn"></a>Macro: <em>int</em> <strong>mpf_sgn</strong> <em>(const mpf_t <var>op</var>)</em></dt>
<dd><a name="index-Sign-tests-2"></a>
<a name="index-Float-sign-tests"></a>
<p>Return <em>+1</em> if <em><var>op</var> &gt; 0</em>, 0 if <em><var>op</var> = 0</em>, and
<em>-1</em> if <em><var>op</var> &lt; 0</em>.
</p>
<p>This function is actually implemented as a macro. It evaluates its argument
multiple times.
</p></dd></dl>
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