I have a periodic signal with TimePeriod~2.3 that is f~.4347
But I am getting another peak at f = 0.
Fs = length(tSol) / (max(tSol)-min(tSol));
L = Fs * (max(tSol) - min(tSol));
P1(2:end-1) = 2*P1(2:end-1);
title('Single-Sided Amplitude Spectrum of X(t)')
Why Is there another peak at f ~ 0?