n = input('Enter n');
t = -n:1:n;
subplot(1,2,1);
y = sin(t)
stem(t,y)
xlabel('n');
ylabel('Amplitude');

n = input('Enter n');
t = -n:1:n;
subplot(1,2,2);
y = cos(t)
stem(t,y)
xlabel('n');
ylabel('Amplitude');

Output

Enter n5
y =
  Columns 1 through 9
    0.9589    0.7568   -0.1411   -0.9093   -0.8415         0    0.8415    0.9093    0.1411
  Columns 10 through 11
   -0.7568   -0.9589

Enter n5
y =
  Columns 1 through 9
    0.2837   -0.6536   -0.9900   -0.4161    0.5403    1.0000    0.5403   -0.4161   -0.9900
  Columns 10 through 11
   -0.6536    0.2837