set terminal svg size 900, 500
set output "coarse_grid0.svg"
set xlabel "Grid points"
set ylabel "Residual value"
set title "Coarse grid correction"
set key outside
set key autotitle columnhead
set pointsize 0.5

plot "coarse_grid.data" index  0 using 1:2 with linespoints lt 1 lw 1