Generate triangular amplitude modulation.
Y = amtriang(N) Y = amtriang(N,T0) Y = amtriang(N,T0,T)
number of points.
time center (default : N/2).
time spreading (default : 2*sqrt(N)).
signal.
amtriang generates a triangular amplitude modulation centered on a time T0, and with a spread proportional to T. This modulation is scaled such that Y(T0)=1.