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wrkdirs::usr...::man::voigt(3)	libcerf	manual	wrkdirs::usr...::man::voigt(3)

NAME
       voigt - Voigt's function, convolution of	Gaussian and Lorentzian

SYNOPSIS
       #include	<cerf.h>

       double voigt ( double x,	double sigma, double gamma );

DESCRIPTION
       The function voigt returns Voigt's convolution

	 voigt(x,sigma,gamma) =	integral G(t,sigma) L(x-t,gamma) dt

       of a Gaussian

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

       and a Lorentzian

	 L(x,gamma) = |gamma| /	pi / ( x^2 + gamma^2 ),

       with the	integral extending from	-infinity to +infinity.

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

       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.

REFERENCES
       Formula (7.4.13)	in Abramowitz &	Stegun (1964) relates Voigt's
       convolution integral to Faddeeva's function w_of_z, upon	which this
       implementation is based:

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

       with

	  z = (x+i*|gamma|) / sqrt(2) /	|sigma|.

SEE ALSO
       voigt_hwhm(3)

       Related complex error functions:	w_of_z(3), dawson(3), cerf(3),
       erfcx(3), erfi(3).

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

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

       Please report bugs to the authors.

COPYING
       Copyright (c) 2013 Forschungszentrum Juelich GmbH

       Software: MIT License.

       This documentation: Creative Commons Attribution	Share Alike.

perl v5.36.3			  2023-08-02	wrkdirs::usr...::man::voigt(3)

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