# set terminal png transparent nocrop enhanced font arial 8 size 420,320 # set output 'fit.13.png' set key bmargin center horizontal Right noreverse enhanced autotitles nobox set title "fitted to realistic model function" set xlabel "Temperature T [deg Cels.]" set ylabel "Density [g/cm3]" l(x) = y0 + m*x high(x) = mh*(x-Tc) + dens_Tc lowlin(x) = ml*(x-Tc) + dens_Tc curve(x) = b*tanh(g*(Tc-x)) density(x) = x < Tc ? curve(x)+lowlin(x) : high(x) y0 = 1.06865074176476 m = -0.000943519626922319 FIT_CONVERGED = 1 FIT_NDF = 31 FIT_STDFIT = 5.38883632121369e-05 FIT_WSSR = 9.00226263801789e-08 ml = -0.00100003889377453 mh = -0.00083126648503697 dens_Tc = 1.02497044445617 Tc = 46.0899249399587 g = 3.85580365358305 b = 0.00153901455759968 plot 'lcdemo.dat', density(x) ## fit density(x) 'lcdemo.dat' via 'start.par'