I have tried using the hilbert command with no luck. I eventually went to just typing in the actual behavior of the frequency response and now I can get plots but they are far from correct I believe. I am not very proficient in MATLAB yet so any help would be appreciated. Thank you.
w1=[0:pi]; w2=[-pi:0]; N=[10 20 40 80]; H1=-j*exp(-j.*N.*w1) H2=j*exp(-j.*N.*w2)
H1i=imag(H1) H1r=real(H1) H2i=imag(H2) H2r=real(H2)
plot(H1i,H1r) hold on plot(H2i,H2r)