# commands1.txt
#
# Usage:
#  gnuplot < commands1.txt
#
set term png
set output 'plot1.png'
set xlabel '<---X--->'
set ylabel '<---Y--->'
set title 'Data versus Vandermonde polynomial interpolant'
set grid
set style data lines
plot 'data1.txt' using 1:2 with points pt 7 ps 2 lc rgb 'blue',\
     'interp1.txt' using 1:2 lw 3 linecolor rgb 'red'