set key off
set xlabel 'Temperature (°C)'
set ylabel 'ADC Value'

f(x) = a*x +b

fit f(x) 'diode.dat' using 1:2 via a, b

set term pngcairo
set output 'diode.png'

p f(x) lt rgb "black" dt 2, \
    'diode.dat' using 1:2 lc rgb "black"