not sure its the right place to write this here or not,but i'll try my luck.
been given an example of plotting a graph,writing this into the command prompt :
L = 31;
nn = 0:(L-1);
imp = zeros(L,1);
imp(1) = 1;
this gives a graphic display.
then i have a few examples to do, the first being x [n]= 0.9∂[n-5] range being 1≤n≤20
could anyone giving a hand,using the example format, then il have a rough idea of trying the others.thanks