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<h1 id="firstHeading" class="firstHeading">crealf, creal, creall</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><complex.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">float crealf( float complex z );</pre>
</td> <td> (1) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">double creal( double complex z );</pre>
</td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">long double creall( long double complex z );</pre>
</td> <td> (3) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dsc-header"> <th> Defined in header <code><tgmath.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">#define creal( z )</pre>
</td> <td> (4) </td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> </table> <div class="t-li1">
<span class="t-li">1-3)</span> Returns the real part of <code>z</code>.</div> <div class="t-li1">
<span class="t-li">4)</span> Type-generic macro: if <code>z</code> has type <code><span class="kw4">long</span> <span class="kw4">double</span> <a href="http://en.cppreference.com/w/c/numeric/complex/complex"><span class="kw743">complex</span></a></code>, <code><span class="kw4">long</span> <span class="kw4">double</span> <a href="http://en.cppreference.com/w/c/numeric/complex/imaginary"><span class="kw745">imaginary</span></a></code>, or <code>long double</code>, <code>creall</code> is called. If <code>z</code> has type <code><span class="kw4">float</span> <a href="http://en.cppreference.com/w/c/numeric/complex/complex"><span class="kw743">complex</span></a></code>, <code><span class="kw4">float</span> <a href="http://en.cppreference.com/w/c/numeric/complex/imaginary"><span class="kw745">imaginary</span></a></code>, or <code>float</code>, <code>crealf</code> is called. If <code>z</code> has type <code><span class="kw4">double</span> <a href="http://en.cppreference.com/w/c/numeric/complex/complex"><span class="kw743">complex</span></a></code>, <code><span class="kw4">double</span> <a href="http://en.cppreference.com/w/c/numeric/complex/imaginary"><span class="kw745">imaginary</span></a></code>, <code>double</code>, or any integer type, <code>creal</code> is called.</div> <h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> z </td> <td> - </td> <td> complex argument </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p>The real part of <code>z</code>.</p>
<p>This function is fully specified for all possible inputs and is not subject to any errors described in <a href="../math/math_errhandling" title="c/numeric/math/math errhandling">math_errhandling</a></p>
<h3 id="Notes"> Notes</h3> <p>For any complex variable <code>z</code>, <code>z <span class="sy1">==</span> creal<span class="br0">(</span>z<span class="br0">)</span> <span class="sy2">+</span> I<span class="sy2">*</span><a href="http://en.cppreference.com/w/c/numeric/complex/cimag"><span class="kw751">cimag</span></a><span class="br0">(</span>z<span class="br0">)</span></code>.</p>
<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h>
#include <complex.h>
int main(void)
{
double complex z = 1.0 + 2.0*I;
printf("%f%+fi\n", creal(z), cimag(z));
}</pre></div> <p>Output:</p>
<div class="text source-text"><pre data-language="c">1.000000+2.000000i</pre></div> </div> <h3 id="References"> References</h3> <ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul>
<li> 7.3.9.6 The creal functions (p: 198-199) </li>
<li> 7.25 Type-generic math <tgmath.h> (p: 373-375) </li>
<li> G.7 Type-generic math <tgmath.h> (p: 545) </li>
</ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul>
<li> 7.3.9.5 The creal functions (p: 180) </li>
<li> 7.22 Type-generic math <tgmath.h> (p: 335-337) </li>
<li> G.7 Type-generic math <tgmath.h> (p: 480) </li>
</ul>
</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="cimag" title="c/numeric/complex/cimag"> <span class="t-lines"><span>cimag</span><span>cimagf</span><span>cimagl</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes the imaginary part a complex number <br> <span class="t-mark">(function)</span> </td>
</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/numeric/complex/real2" title="cpp/numeric/complex/real2">C++ documentation</a></span> for <code>real</code> </td>
</tr> </table> <div class="_attribution">
<p class="_attribution-p">
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