## Spectral Bin Numbers

Since the th spectral sample
is properly regarded as
a measure of spectral amplitude over a *range* of frequencies,
nominally to , this range is sometimes called a
*frequency bin*
(as in a ``storage bin'' for spectral energy).
The frequency index is called the *bin number*, and
can be regarded as the total energy in the th
bin (see §7.4.9).
Similar remarks apply to samples of any
bandlimited
function; however, the term ``bin'' is only used in the frequency
domain, even though it could be assigned exactly the same meaning
mathematically in the time domain.

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Fourier Series Special Case

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Frequencies in the ``Cracks''