# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 500, 350 
# set output 'simple.8.png'
set key bmargin left horizontal Right noreverse enhanced autotitles box linetype -1 linewidth 1.000
set samples 800, 800
plot [-19:19] '1.dat'with impulses ,'2.dat' ,'3.dat' with lines