problem in ploting charts

hey there,

this is my code every thing works good with no errors.

but show me some charts az empty, how to fix

is it related to : the Equation doesnt have real value?

code :

syms t
x1 = @(t) (exp(-t) * heaviside(t));
X_w = fourier(x1(t))
h = @(t) heaviside(t + 1) - heaviside(t - 1);
H_w = fourier(h(t))
Y_w = (X_w)*(H_w)
y1 = ifourier(Y_w)

 
subplot(2, 4, 1);
fplot(X_w, [0, 2*pi]);
grid on;
xlabel("w");
ylabel("X(w)");

subplot(2, 4, 2);
fplot(H_w);
grid on;
xlabel("w");
ylabel("H(w)");

subplot(2, 4, 3);
fplot(Y_w);
grid on;
xlabel("w");
ylabel("Y1(w)");

subplot(2, 4, 4);
fplot(y1);
grid on;
xlabel("t");
ylabel("y1(t)");

Answer 1

[Takumi]

All parts other than y1 are complex, so the real or imaginary part must be specified.

eg. real(X_w)