set term svg ;
set out 'Out.splines.svg';
set xlabel 'x';
set ylabel 'y';
set key right bottom;
set tics out;
set title 'Linear/quadratic/cubic splines of random data';
plot 'out.data.txt' index 0 with points title 'data',
'out.data.txt' index 1 using 1:2 with lines title 'linear spline',
'out.data.txt' index 1 using 1:3 with lines title 'quadratic spline',
'out.data.txt' index 1 using 1:4 with lines title 'cubic spline',
'out.data.txt' index 0 smooth csplines lw 4 dashtype (10,
10) title 'gnuplot cubic spline'