# plotting phase transformations of a signal

I would like to find the phase variations of the signal with respect to time axes:

S = sin(2*pi*100*t + pi/4) + cos(pi*500*t) + sin(2*pi*100*t + 5*pi/2);

This is a real signal, so the phase can only be $$0$$ to $$\pi$$.
• what is actually the angle(fft(S)) giving? – jomegaA Feb 7 at 8:54
• @Shaheena Please define what you are referring to as "phase variation". In my definition you would need to have a complex signal to have any phase results other than $0$ o $pi$; the arg expression in MATLAB and Octave is consistent with this--it returns the phase versus time and for your signal would be $0$ or $pi$ only. – Dan Boschen Feb 7 at 12:08