set terminal png
set output 'heating.png'
set xdata time
set timefmt "%b %d %H:%M:%S %Y"
set title "Radiant Heating System Internal Temperatures" 
set ylabel "Fahrenheit" 
set yrange [30:125]
set xrange [*:*]
set xlabel " "
set grid
set size 1.2 ,0.5
set key top left

heat_on(a, b, c, d) = int(a) | int(b) | int(c) | int(d)

plot 'housetemps.input' using 1:5 t "Outside" with lines lc rgb "black", \
     'munchkin_temperature.data' using 1:(($6 * 1.8) + 32) t "Supply" with lines, \
     'munchkin_temperature.data' using 1:(($5 * 1.8) + 32) t "Return" with lines, \
     'zone.data' using 1:(heat_on($5,$7,$8,$9) * (1 - $6) * 35) t "Gas Heat" with points lc rgb "blue", \
     'zone.data' using 1:(heat_on($5,$7,$8,$9) * $6 * 35) t "Solar Heat" with points lc rgb "brown"