I have some real data (data packets in a router). When I plot it I can see there is a clear periodicity on the dataset (24hours+-).
But how can I discover the periodicity of the data without being by approximation, and possible check other periodicities?
What I am trying to do:
I thought I just had to do the the Fourier transform and then see what were the higher frequencies (one should be around 24).
When I do this in octave and then plot the graphic only garbage comes out.
What am I doing wrong?