I was wondering if someone knows how to generate many sine waves at once (I also need to add them), for example, to generate 2 I use:

s_1 = (exp(j*2*pi*f_1*t) - exp(-j*2*pi*f_1*t))/(2*j);

s_2 = imag(exp(j*2*pi*f_2*t));

% plot the 2 and 4 Hz waves together in the same panel

figure

subplot(2,1,1)

plot(t,s_1, 'b-')

hold on

plot(t, s_2, 'r--')

ylabel('Amplitude')

% Plot the sum

subplot(2,1,2)

plot(t, s_1+s_2)

ylabel('Amplitude')

xlabel('Time (s)')

How can I do this without using Hold on.

Thank you