t = (0:10:.05)';
x = exp (-0.5*t) .* (cos (2*pi*3*t) + sin (2*pi*7*t));
X = fft (x);
rfile faxis
freq = faxis (X, .05, 3);
mag = abs (X);
rfile angle
phase = angle (X);
pstart (1,2,"xwin");

ptitle ("Magnitude of FFT")
xlabel ("Frequency (Hertz)");
plwid(6);
plot ([freq,mag]);

ptitle ("Angle (atan2(imag/real)) of FFT")
xlabel ("Frequency (Hertz)");
ylabel ("Angle (radians)");
plwid(6);
plot ([freq,phase]);
plprint ("p3.ps");
