+set term png size 800,480
+
+set datafile separator ";"
+
+set ylabel "Voltage (mV)"
+
+datafile = "logfile.log"
+
+samples(x) = $0 > 4 ? 5 : ($0+1)
+avg5(x) = (shift5(x), (back1 + back2 + back3 + back4 + back5) / samples($0))
+shift5(x) = (back5 = back4, \
+ back4 = back3, \
+ back3 = back2, \
+ back2 = back1, \
+ back1 = x)
+init(x) = (back1 = back2 = back3 = back4 = back5 = sum = 0)
+
+plot sum=init(0), \
+ datafile using (avg5($7 - ($7 + $8 + $9) / 3)), \
+ datafile using (avg5($8 - ($7 + $8 + $9) / 3)), \
+ datafile using (avg5($9 - ($7 + $8 + $9) / 3))