• In mathematics, Parseval's theorem usually refers to the result that the Fourier transform is unitary; loosely, that the sum (or integral) of the square...
    9 KB (1,813 words) - 00:44, 11 June 2025
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    the star denotes complex conjugation. The Plancherel theorem is a special case of Parseval's theorem and states: ∑ n = 0 N − 1 | x n | 2 = 1 N ∑ k = 0 N...
    76 KB (12,338 words) - 04:38, 31 July 2025
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    Plancherel, it is still often referred to as Parseval's formula, or Parseval's relation, or even Parseval's theorem. See Pontryagin duality for a general formulation...
    177 KB (21,320 words) - 20:50, 1 August 2025
  • square-integrable over the interval ( 0 , ∞ ) {\displaystyle (0,\infty )} , then Parseval's formula holds: ∫ 0 ∞ f 1 ( x ) f 2 ( x ) d x = 1 2 π i ∫ c − i ∞ c + i...
    33 KB (4,679 words) - 18:09, 17 June 2025
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    p_{N}(x)=\sum _{n=-N}^{N}p[n]\ e^{i2\pi {\tfrac {n}{P}}x}.} Parseval's theorem implies that: Theorem—The trigonometric polynomial s N {\displaystyle s_{N}}...
    72 KB (11,152 words) - 20:53, 30 July 2025
  • {d} r=\int _{0}^{\infty }F_{\nu }(k)G_{\nu }(k)\,k\,\mathrm {d} k.} Parseval's theorem, which states ∫ 0 ∞ | f ( r ) | 2 r d r = ∫ 0 ∞ | F ν ( k ) | 2 k...
    26 KB (4,204 words) - 21:10, 3 February 2025
  • In mathematical analysis, Parseval's identity, named after Marc-Antoine Parseval, is a fundamental result on the summability of the Fourier series of a...
    5 KB (796 words) - 22:55, 2 February 2025
  • \max(-\beta _{1},\alpha _{2})<c<\min(-\alpha _{1},\beta _{2})} . Then Parseval's theorem holds: ∫ − ∞ ∞ f 1 ( t ) ¯ f 2 ( t ) d t = 1 2 π i ∫ c − i ∞ c + i...
    18 KB (1,995 words) - 01:40, 28 February 2025
  • correct in SI units for spectral energy density. As a consequence of Parseval's theorem, one can prove that the signal energy is always equal to the summation...
    4 KB (538 words) - 21:57, 17 May 2025
  • Marc-Antoine Parseval des Chênes (27 April 1755 – 16 August 1836) was a French mathematician, most famous for what is now known as Parseval's theorem, which...
    4 KB (367 words) - 13:40, 21 January 2025
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    x(t)} is a square-integrable function) allows applying Parseval's theorem (or Plancherel's theorem). That is, ∫ − ∞ ∞ | x ( t ) | 2 d t = ∫ − ∞ ∞ | x ^...
    37 KB (5,896 words) - 00:17, 5 August 2025
  • _{n=0}^{\infty }|c_{n}|^{2}\leq \int _{a}^{b}|f(x)|^{2}w(x)\,dx.} Parseval's theorem usually refers to the result that the Fourier transform is unitary;...
    9 KB (1,582 words) - 15:40, 25 February 2025
  • generalization of Parseval's theorem; often used in the fields of science and engineering, proving the unitarity of the Fourier transform. The theorem states that...
    7 KB (1,197 words) - 05:57, 7 May 2025
  • _{M}} A special case of the Parseval's theorem is when the two multi-dimensional signals are the same. In this case, the theorem portrays the energy conservation...
    24 KB (4,602 words) - 04:59, 25 March 2025
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    Parallelogram law Parseval's identity – The energy of a periodic function is the same in the time and frequency domain. Ptolemy's theorem – Relates the 4...
    95 KB (12,798 words) - 21:40, 4 August 2025
  • Lauricella's theorem (functional analysis) Paley–Wiener theorem (Fourier transforms) Parseval's theorem (Fourier analysis) Plancherel theorem (Fourier analysis)...
    78 KB (6,296 words) - 20:31, 6 July 2025
  • function, and finally applying the inverse Fourier transform. Hence Parseval's theorem easily shows that the Hilbert transform is bounded from L 2 {\displaystyle...
    9 KB (1,488 words) - 16:48, 27 March 2025
  • such as LUFs. The RMS can be computed in the frequency domain, using Parseval's theorem. For a sampled signal x [ n ] = x ( t = n T ) {\displaystyle x[n]=x(t=nT)}...
    19 KB (2,786 words) - 10:02, 9 April 2025
  • Exponential sum Dirichlet kernel Fejér kernel Gibbs phenomenon Parseval's identity Parseval's theorem Weyl differintegral Generalized Fourier series Orthogonal...
    3 KB (202 words) - 12:10, 30 October 2023
  • theorems, including Parseval's theorem. For this reason, keeping the full name of "Rayleigh Theorem for Eigenvalues" avoids confusions. The theorem,...
    22 KB (3,103 words) - 12:13, 12 April 2025
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    f ) {\displaystyle H(f)} or in the time domain by exploiting the Parseval's theorem with the system impulse response h ( t ) {\displaystyle h(t)} . If...
    16 KB (2,296 words) - 06:40, 8 May 2025
  • Fourier transform (with proper normalization). This follows from Parseval's theorem. Quantum logic gates are unitary operators. Not all gates are Hermitian...
    9 KB (1,312 words) - 12:33, 12 April 2025
  • Thumbnail for Spherical harmonics
    related to its spectral coefficients by a generalization of Parseval's theorem (here, the theorem is stated for Schmidt semi-normalized harmonics, the relationship...
    75 KB (12,488 words) - 23:57, 29 July 2025
  • satisfy Parseval's theorem. (Other, non-unitary, scalings, are also commonly used for computational convenience; e.g., the convolution theorem takes on...
    11 KB (2,115 words) - 21:03, 14 April 2025
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    {\displaystyle \epsilon } , can be derived using Plancherel theorem or Parseval's theorem for the Fourier transform. If we substitute in the expression...
    7 KB (1,319 words) - 19:16, 11 July 2025
  • n-ball. Choosing ρ to minimize the sum of (1) and (2) and applying Parseval's theorem: ‖ u ^ ‖ L 2 = ‖ u ‖ L 2 {\displaystyle \|{\hat {u}}\|_{L^{2}}=\|u\|_{L^{2}}}...
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  • which has the largest multiplier space. This is the easiest case. Parseval's theorem allows to solve this problem completely and obtain that a function...
    25 KB (2,817 words) - 04:01, 19 July 2025
  • This form of the Riesz–Fischer theorem is a stronger form of Bessel's inequality, and can be used to prove Parseval's identity for Fourier series. Other...
    11 KB (1,885 words) - 16:45, 2 April 2025
  • operator Fourier inversion theorem Sine and cosine transforms Parseval's theorem Paley–Wiener theorem Projection-slice theorem Frequency spectrum Discrete...
    3 KB (224 words) - 19:08, 14 September 2024
  • Bessel's inequality (category Theorems in functional analysis)
    finite}}{\Bigr \}}\leq \lVert x\rVert ^{2}.} Cauchy–Schwarz inequality Parseval's theorem "Bessel inequality - Encyclopedia of Mathematics". Saxe, Karen (2001-12-07)...
    7 KB (1,375 words) - 17:19, 3 August 2025