I have a long signal (1 day sampled at 500 Hz), which results in many frequencies if I calculate the amplitude spectrum (see e.g. here). However, I am only interested in the "big picture", let's say only frequencies of natural numbers (i.e. 1, 2, ..., 250 Hz).
Should I simply remove all other frequencies? Should I do something like a binning? Or is there even a better solution?