The discrete Fourier-Transform an $L^p$ approximation of functions.
نویسندگان
چکیده
منابع مشابه
The Discrete Fourier Transform∗
1 Motivation We want to numerically approximate coefficients in a Fourier series. The first step is to see how the trapezoidal rule applies when numerically computing the integral (2π) −1 2π 0 F (t)dt, where F (t) is a continuous, 2π-periodic function. Applying the trapezoidal rule with the stepsize taken to be h = 2π/n for some integer n ≥ 1 results in (2π) −1 2π 0 F (t)dt ≈ 1 n n−1 j=0 Y j , ...
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ژورنال
عنوان ژورنال: MATHEMATICA SCANDINAVICA
سال: 1975
ISSN: 1903-1807,0025-5521
DOI: 10.7146/math.scand.a-11576