0 0.3535
1 0.3535
2 0.6464
3 1.0607
4 0.3535
5 -1.0607
6 -1.3535
7 -0.3535

set key off
set xlabel 'n'
set ylabel 'x(n)'
set grid
set size ratio 0.5
plot [-0.5:7.5] [-2:2] '1.dat' with points pointtype 5

gnuplot -p -e "set key off; set xlabel 'n'; set ylabel 'x(n)'; set grid; set size ratio 0.5; plot [-0.5:7.5] [-2:2] '1.dat' with points pointtype 5"

0 0.0
1 4.0
2 2.0
3 0.0
4 0.0
5 0.0
6 2.0
7 4.0

set key off
set xlabel "m (kHz)"
set ylabel "X(m)"
set size rate 0.5
plot [0:7.1] [0:6] '2.dat' with impulses lw 3, '2.dat' pt 5

gnuplot -p -e "set key off; set xlabel 'm(kHz)'; set ylabel 'X(m)'; set grid;set size ratio 0.5; plot [-0.5:7.5] [0:5] '2.dat' with impulses lw 3, '2.dat' pt 5"