reset set title 'Interpolation on a regular grid' ftitle(a,b) = sprintf("%.0f/x^{%4.2f}", exp(a), -b) f(x)=a+b*x fit f(x) 'log' u (log($1)):(log($2)) via a,b set xlabel 'Maximum resolution' set ylabel 'Maximum error' set logscale set cbrange [1:2] set xrange [16:512] set xtics 16,2,512 set grid ytics plot 'log' u 1:2 t '', exp(f(log(x))) t ftitle(a,b)