#Set the name of the file for the graph
set term pdf
set out 'steelout.pdf'

#The lines below fit the data
T0=100
g=0.03
f(x) = T0*exp(-g*x)
fit f(x) 'steelcool.txt' using 1:4 via T0, g

#The lines below graph the data and the fit
set grid
set key at screen 0.9, 0.9
set xlabel 'Time(sec)'
set ylabel 'Temp Difference (deg C)'
set xrange [0:100]
plot 'steelcool.txt' using 1:4 with points pt 7 ps 0.3 t 'Data',\
f(x) t 'Fit'