# This plots a long-running dataset, i.e. from 1:20 A.M. to 10 A.M.
# The time offset, which is added while plotting.
#
# Run: gnuplot --persist -c example2.gp

# Time offset in seconds since 1:20 A.M.:
t_offset=3600 + 1200

# Use a common function for the time axis with both plots
rt(x) = x + t_offset

# Show percentage from values
pc(x, c) = 100 * x / c

#set term wxt 0 title 'RPi : Temperature & Light'
set datafile separator ","
set xdata time
set timefmt "%s"
set xlabel "Time (hh:mm)"

set yrange [0:24]
set ytics nomirror
set ylabel "Temp (°C)"

set y2range [0:110]
set y2tics nomirror
set format y2 '%2.0f%%'
set y2label "Light"

set key right bottom

# Show light as a percentage of the maximum sensed value
plot 'ttyACM0-870.csv' using (rt($1)):2 with lines title "Temp", \
     'ttyACM0-870.csv' using (rt($1)):(pc($3, 1.1)) with lines axes x1y2 title "Light"