This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.
 FOURIER SERIES PACKAGE SYMBOL

# NFourierTrigSeries

 gives a numerical approximation to the order n Fourier trigonometric series expansion of expr, where expr is a periodic function of t with period .
• The numerical approximation to the order n Fourier exponential series expansion of expr is by default defined to be c0+ckCos[k t]+dk Sin[k t].
• The coefficient is defined to be NIntegrate[expr Cos[k t], {t, -, }] and the coefficient is defined to be NIntegrate[expr Sin[k t], {t, -, }].
• Different choices for the period of expr can be specified using the option FourierParameters.
• With the setting FourierParameters, expr is assumed to have a period of , and the order n Fourier exponential series expansion computed by is (+ck Cos[2 b k t]+dk Sin[2 b k t]). Here, the coefficient is defined to be NIntegrate[expr Cos[b k t], {t, -, }] and the coefficient is defined to be NIntegrate[expr Sin[b k t], {t, -, }].
Numerical approximation for a trigonometric Fourier series:
Compare with a plot of the original function:
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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