This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
 Fourier Series Package Symbol

# 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 1.
• 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 periodic function:
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