Self-Starting nls Pseudo-Voigt model

Pseudo-Voigt peak function.

SSpsVoigt1(input,y0, A, nu, xc, w)

Arguments

input

a numeric vector of values at which to evaluate the model.
y0

offset
A

area
nu

is the mixing parameter, 0 is Gauss and 1 is Lorentz, if nu>1 this is called a super Lorentzian.
xc

center
w

width

Value

a numeric vector of the same length as input. It is the value of the expression y0+A*((nu*2*w)/(pi*4*(x-xc)^2+w^2)+(1-nu)*(sqrt(4*log(2))*exp((-4*log(2)*(x-xc)^2)/w^2))/sqrt(pi*w)).

Note

This is primarily intended for use in formulae given to the nls function or similar functions for example mle2.

References

qtiplot: https://www.qtiplot.com/doc/manual-en/x9885.html.

See also

selfStart, getInitial

Examples

data(smoking)
model <- nlsLM(USA ~ SSpsVoigt1(year,y0,A,nu,xc,w),data=smoking)