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libcerf-devel-1.13-3.mga7.armv7hl.rpm

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<h1 id="NAME">NAME</h1>

<p>voigt - Voigt&#39;s function, convolution of Gaussian and Lorentzian</p>

<h1 id="SYNOPSIS">SYNOPSIS</h1>

<p><b>#include &lt;cerf.h</b>&gt;</p>

<p><b>double voigt ( double x, double sigma, double gamma );</b></p>

<h1 id="DESCRIPTION">DESCRIPTION</h1>

<p>The function <b>voigt</b> returns Voigt&#39;s convolution</p>

<pre><code>  voigt(x,sigma,gamma) = integral G(t,sigma) L(x-t,gamma) dt</code></pre>

<p>of a Gaussian</p>

<pre><code>  G(x,sigma) = 1/sqrt(2*pi)/|sigma| * exp(-x^2/2/sigma^2)</code></pre>

<p>and a Lorentzian</p>

<pre><code>  L(x,gamma) = |gamma| / pi / ( x^2 + gamma^2 ),</code></pre>

<p>with the integral extending from -infinity to +infinity.</p>

<p>If sigma=0, L(x,gamma) is returned. Conversely, if gamma=0, G(x,sigma) is returned.</p>

<p>If sigma=gamma=0, the return value is Inf for x=0, and 0 for all other x. It is advisable to test input arguments to exclude this irregular case.</p>

<h1 id="REFERENCES">REFERENCES</h1>

<p>Formula (7.4.13) in Abramowitz &amp; Stegun (1964) relates Voigt&#39;s convolution integral to Faddeeva&#39;s function <b>w_of_z</b>, upon which this implementation is based:</p>

<pre><code>   voigt(x,sigma,gamma) = Re[w(z)] / sqrt(2*pi) / |sigma|</code></pre>

<p>with</p>

<pre><code>   z = (x+i*|gamma|) / sqrt(2) / |sigma|.</code></pre>

<h1 id="SEE-ALSO">SEE ALSO</h1>

<p><b>voigt_hwhm(3)</b></p>

<p>Related complex error functions: <b>w_of_z(3)</b>, <b>dawson(3)</b>, <b>cerf(3)</b>, <b>erfcx(3)</b>, <b>erfi(3)</b>.</p>

<p>Homepage: http://apps.jcns.fz-juelich.de/libcerf</p>

<h1 id="AUTHORS">AUTHORS</h1>

<p>Joachim Wuttke &lt;j.wuttke@fz-juelich.de&gt;, Forschungszentrum Juelich, based on the w_of_z implementation by Steven G. Johnson, http://math.mit.edu/~stevenj, Massachusetts Institute of Technology.</p>

<p>Please report bugs to the authors.</p>

<h1 id="COPYING">COPYING</h1>

<p>Copyright (c) 2013 Forschungszentrum Juelich GmbH</p>

<p>Software: MIT License.</p>

<p>This documentation: Creative Commons Attribution Share Alike.</p>


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