reset

set encoding iso_8859_1
set title "Widerstand der Feldplatte in Abhängigkeit von B"
set xlabel "[B in T]"
set ylabel "[R_{f} in {/Symbol W}]"
set grid xtics ytics
set key top left

R_v = 25e3
U_0 = 6.35
U_f_0 = 26e-3
R_f_0 = R_v * U_f_0/(U_0 - U_f_0)

f(x) = a*x**2 + b*x + c
fit f(x) 'DatenErregerstrom.txt' us ($2):(R_v * (($3) / 1000)/(U_0 - (($3) / 1000))) via a,b,c

plot \
'DatenErregerstrom.txt' us ($2):(R_v * ($3 / 1000)/(U_0 - ($3 / 1000))) notitle lt 1, \
f(x) title "Ausgleichsparabel" lt 3

set output "widerstand_feldplatte.eps"
set term postscript enhanced eps color; replot