1builddir::build::BUILD::libbcueirlfd-dvli1ir.b:1c:3eb:ru:fimlamdna::n::uBvaUolIiLgDt:(:3l)ibcerf-v1.13::man::voigt(3)
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6 voigt - Voigt's function, convolution of Gaussian and Lorentzian
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9 #include <cerf.h>
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11 double voigt ( double x, double sigma, double gamma );
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14 The function voigt returns Voigt's convolution
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16 voigt(x,sigma,gamma) = integral G(t,sigma) L(x-t,gamma) dt
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18 of a Gaussian
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20 G(x,sigma) = 1/sqrt(2*pi)/|sigma| * exp(-x^2/2/sigma^2)
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22 and a Lorentzian
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24 L(x,gamma) = |gamma| / pi / ( x^2 + gamma^2 ),
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26 with the integral extending from -infinity to +infinity.
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28 If sigma=0, L(x,gamma) is returned. Conversely, if gamma=0, G(x,sigma)
29 is returned.
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31 If sigma=gamma=0, the return value is Inf for x=0, and 0 for all other
32 x. It is advisable to test input arguments to exclude this irregular
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36 Formula (7.4.13) in Abramowitz & Stegun (1964) relates Voigt's
37 convolution integral to Faddeeva's function w_of_z, upon which this
38 implementation is based:
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40 voigt(x,sigma,gamma) = Re[w(z)] / sqrt(2*pi) / |sigma|
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42 with
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44 z = (x+i*|gamma|) / sqrt(2) / |sigma|.
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47 voigt_hwhm(3)
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49 Related complex error functions: w_of_z(3), dawson(3), cerf(3),
50 erfcx(3), erfi(3).
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52 Homepage: http://apps.jcns.fz-juelich.de/libcerf
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55 Joachim Wuttke <j.wuttke@fz-juelich.de>, Forschungszentrum Juelich,
56 based on the w_of_z implementation by Steven G. Johnson,
57 http://math.mit.edu/~stevenj, Massachusetts Institute of Technology.
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59 Please report bugs to the authors.
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62 Copyright (c) 2013 Forschungszentrum Juelich GmbH
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64 Software: MIT License.
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66 This documentation: Creative Commons Attribution Share Alike.
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70perl v5.30.0 builddir2:0:1b9u-i0l7d-:2:5BUILD::libcerf-v1.13::man::voigt(3)