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NFourierTrigSeries

NFourierTrigSeries[expr, t, k]
gives a numerical approximation to the order n Fourier trigonometric series expansion of expr, where expr is a periodic function of t with period 2 pi.
  • The numerical approximation to the order n Fourier exponential series expansion of expr is by default defined to be .
  • The coefficient ck is defined to be and the coefficient dk is defined to be .
  • Different choices for the period of expr can be specified using the option FourierParameters.
  • With the setting FourierParameters->{a, b}, expr is assumed to have a period of , and the order n Fourier exponential series expansion computed by NFourierTrigSeries is . Here, the coefficient ck is defined to be and the coefficient dk is defined to be .
Needs["FourierSeries`"]
Numerical approximation for a trigonometric Fourier series:
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Compare with a plot of the original function:
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