set terminal png size 600,250

set xdata time
set timefmt "%s"

set pointsize 0.2

set output '/dev/shm/1.png'
plot "/dev/shm/temp.tsv" using 1:2 with points title "DS18B20 deg. C","/dev/shm/temp.tsv" using 1:($3 > 1 && $3 < 45 ? $3 : '') with dots title "DHT22 deg. C"

set output '/dev/shm/2.png'
plot "/dev/shm/temp.tsv" using 1:($3 > 1 && $3 < 45 ? $3 : '') with dots title "DHT22 deg. C"

set output '/dev/shm/3.png'
plot "/dev/shm/temp.tsv" using 1:($4 > 3 ? $4 : '') with dots title "DHT22 % hum"