stat 'wzrost_studentow-dane.txt'
show variable
print STATS_mean, STATS_ssd
u=STATS_mean
sigma=STATS_ssd
f(x)=1/(sqrt(2*pi)*sigma)*exp(-(x-u)**2/(2*sigma**2))
plot 'wzrost_studentow_bins.txt' using 1:2:3 with yerrorbars
fit f(x) 'wzrost_studentow_bins.txt' u 1:2 via u, sigma
set xlabel 'wzrost [cm]'
set ylabel 'częstość'
set title 'histogram wzrostu studentów'
plot 'wzrost_studentow_bins.txt' using 1:2:3 with yerrorbars pt 5 title 'dane', f(x)