same problem lies here where fs=1000
fs = 1000; % samplig frequency [Hz]
t = 0:1/fs:0.1-1/fs; % time vector
w = 267*pi; % oscilation frequency [rad/s] (133.5 Hz)
p = 1.2; % phase [rad] (68.7549 deg)
x = 10*cos(w*t+p); % wave vector
N=length(x); % N:number of values
r=zeros(1,3); % r={r0,r1,r2}
for k=0:2, % k=0,1,2
n=(0:N-1-k);
r(k+1) = sum(x(n+1).*x(n+1+k))/(N-k);
end
w0 = fs*acos((r(3)+sqrt(r(3)^2+8*r(2)^2))/(4*r(2))); % [rad/s]
fprintf('w0 = %f rad/s = %f Hz\n',w0,w0/2/pi);
now i want to replace x = 10*cos(267*pi*t+1.2) by the third column imported from a text file as shown above.
Fs now Fs becomes 1.the code now is changed into
ssn = spot_num(:,3);
ssn = ssn-mean(ssn);
x=ssn;
N=max(size(x));
N=length(x); % N:number of values
r=zeros(1,3); % r={r0,r1,r2}
for k=0:2, % k=0,1,2
n=(0:N-1-k);
r(k+1) = sum(x(n+1).*x(n+1+k))/(N-k);
end
w0 = fs*acos((r(3)+sqrt(r(3)^2+8*r(2)^2))/(4*r(2))); % [rad/s]
fprintf('w0 = %f rad/s = %f Hz\n',w0,w0/2/pi);
once again the output is not consistent to model answer. so what happens then?
