| Harmonic Analysis |
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| q | Harmonic analysis is used to identify the periodic (regular)
variations in |
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| geophysical time series. |
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| q | If we have N observations of (xi,
yi), the time series y(t)
can be |
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| approximated by cosine and sine functions : |
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| q | How many harmonics (cosine/sine functions) do we
need? |
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| In general, if the
number of observations is N, the number of harmonic |
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| equal to N/2 (pairs of cosine and sine functions). |
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