When we have a frequency response (or transfer function) for a system we often want to use it to plot the magnitude and phase response of the system. To do

so in MATLAB we make use of the abs and angle commands. For a system frequency response given in analytical form, H\left(e^{j \omega}\right)=1+e^{-j \omega} > H = 1 + exp(-j.*w); figure (3); subplot (2,1 ,1); > plot (w, abs (H)); > аxis ([—pi рі 0 2]); > xlabel('$$\omega$$' , ' interpreter ', 'latex '); > title ('$$ | H(e^{j\omega})| $$ ' , ' interpreter ','latex '); subplot (2,1 ,2); > plot (w, angle (H)); ахis ([— pi рі —1.75 1.75]); xlabel('$$\omega$$', 'interpreter ','latex '); title (' $$\angle H(e^{j\omega}) $$ ' , ' interpreter ','latex '); In this case notice that we have used the plot command. Even though these are discrete sequences it is conventionally acceptable to plot the magnitude and phase response as continuous functions. Also notice that we have only plotted the response plots from [-7, 7]. One of the consequences of sampling is that the Discrete-Time Fourier Transform is27-periodic and hence we only need to plot from [-a, 7]. This will become clear later in the semester.