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<h1 id="firstHeading" class="firstHeading">cabsf, cabs, cabsl</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 cabsf( 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 cabs( 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 cabsl( 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 fabs( 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> Computes the complex absolute value (also known as norm, modulus, or magnitude) 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> or <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>, <code>cabsl</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> or <code><span class="kw4">float</span> <a href="http://en.cppreference.com/w/c/numeric/complex/imaginary"><span class="kw745">imaginary</span></a></code>, <code>cabsf</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> or <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>cabs</code> is called. For real and integer types, the corresponding version of <code><a href="../math/fabs" title="c/numeric/math/fabs">fabs</a></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>If no errors occur, returns the absolute value (norm, magnitude) of <code>z</code>.</p>
<p>Errors and special cases are handled as if the function is implemented as <code><a href="http://en.cppreference.com/w/c/numeric/math/hypot"><span class="kw667">hypot</span></a><span class="br0">(</span><a href="http://en.cppreference.com/w/c/numeric/complex/creal"><span class="kw754">creal</span></a><span class="br0">(</span>z<span class="br0">)</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><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 + 1.0*I;
printf("%.1f%+.1fi cartesian is rho=%f theta=%f polar\n",
creal(z), cimag(z), cabs(z), carg(z));
}</pre></div> <p>Output:</p>
<div class="text source-text"><pre data-language="c">1.0+1.0i cartesian is rho=1.414214 theta=0.785398 polar</pre></div> </div> <h3 id="References"> References</h3> <ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul>
<li> 7.3.8.1 The cabs functions (p: 195) </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> 7.3.8.1 The cabs functions (p: 177) </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="carg" title="c/numeric/complex/carg"> <span class="t-lines"><span>carg</span><span>cargf</span><span>cargl</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 phase angle of a complex number <br> <span class="t-mark">(function)</span> </td>
</tr> <tr class="t-dsc"> <td> <div><a href="../math/abs" title="c/numeric/math/abs"> <span class="t-lines"><span>abs</span><span>labs</span><span>llabs</span></span></a></div>
<div><span class="t-lines"><span><span class="t-mark-rev t-since-c99">(C99)</span></span></span></div> </td> <td> computes absolute value of an integral value (\(\small{|x|}\)|x|) <br> <span class="t-mark">(function)</span> </td>
</tr> <tr class="t-dsc"> <td> <div><a href="../math/fabs" title="c/numeric/math/fabs"> <span class="t-lines"><span>fabs</span><span>fabsf</span><span>fabsl</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></div> </td> <td> computes absolute value of a floating-point value (\(\small{|x|}\)|x|) <br> <span class="t-mark">(function)</span> </td>
</tr> <tr class="t-dsc"> <td> <div><a href="../math/hypot" title="c/numeric/math/hypot"> <span class="t-lines"><span>hypot</span><span>hypotf</span><span>hypotl</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 square root of the sum of the squares of two given numbers (\(\scriptsize{\sqrt{x^2+y^2} }\)<span class="t-mrad"><span>√</span><span>x<sup class="t-su">2</sup>+y<sup class="t-su">2</sup></span></span>) <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/abs" title="cpp/numeric/complex/abs">C++ documentation</a></span> for <code>abs</code> </td>
</tr> </table> <div class="_attribution">
<p class="_attribution-p">
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