MATLAB: Function sinc in matlab

Question

I have this signal shifted by 7000 on the t axis

g(t) = 4000 * sinc(4000 * t) * e^(j * 2 * pi * 7000 * t)

I tried to replicate this in matlab to get the sinc graph, but does not work:

j = sqrt(-1);
x = linspace(-9000,9000);
y = (4000 * sinc(4000 * x)) * (exp(j * 2 * pi *7000 * x));
plot(x,y)
grid

Can anyone help me? Thanks!

Answer 1

y = (4000 * sinc(4000 * x)) .* (exp(j * 2 * pi *7000 * x)); % .*!!

Note: By default j is an imaginary number in MATLAB