Summary

Cumulative distribution function (cdf) of a folded-normal random variable with ${\displaystyle \mu =1}$, ${\displaystyle \sigma =1}$. The graph is generated using gnuplot:

set terminal svg enhanced size 640 360
set samples 1001  # high quality
set border 31 linewidth .3 # thin border
set output "folded_normal.svg"

set notitle
set xrange [-3:5]

set ytics 0.1

cdf_normal(x,m,s)=0.5+0.5*erf((x-m)/s/sqrt(2.0))

sigma=1.0
mu=1.0

cdf_fn(x)= (x<0) ? 0 : cdf_normal(x,mu,sigma)-cdf_normal(-x,mu,sigma)

set arrow 1 from  0,0 to  0,1.0 nohead lt 0
plot	cdf_normal(x,mu,sigma) title "normal",\
	cdf_fn(x) title "folded-normal" lw 3
	

Licensing

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