# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 512, 280 
# set output 'transparent.1.png'
set clip two
set style fill   solid 1.00 noborder
set key title "Gaussian Distribution"
set key inside left top vertical Left reverse enhanced autotitles nobox
set key noinvert samplen 1 spacing 1 width 0 height 0 
set style function filledcurves y1=0
set title "Solid filled curves" 
set xrange [ -5.00000 : 5.00000 ] noreverse nowriteback
set yrange [ 0.00000 : 1.00000 ] noreverse nowriteback
unset colorbox
Gauss(x,mu,sigma) = 1./(sigma*sqrt(2*pi)) * exp( -(x-mu)**2 / (2*sigma**2) )
d1(x) = Gauss(x, 0.5, 0.5)
d2(x) = Gauss(x,  2.,  1.)
d3(x) = Gauss(x, -1.,  2.)
GPFUN_Gauss = "Gauss(x,mu,sigma) = 1./(sigma*sqrt(2*pi)) * exp( -(x-mu)**2 / (2*sigma**2) )"
GPFUN_d1 = "d1(x) = Gauss(x, 0.5, 0.5)"
GPFUN_d2 = "d2(x) = Gauss(x,  2.,  1.)"
GPFUN_d3 = "d3(x) = Gauss(x, -1.,  2.)"
plot d1(x) fs solid 1.0 lc rgb "forest-green" title "μ =  0.5 σ = 0.5",      d2(x) lc rgb "gold" title "μ =  2.0 σ = 1.0",      d3(x) lc rgb "red" title "μ = -1.0 σ = 2.0"