enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Fourier transform - Wikipedia

    en.wikipedia.org/wiki/Fourier_transform

    The trade-off between the compaction of a function and its Fourier transform can be formalized in the form of an uncertainty principle by viewing a function and its Fourier transform as conjugate variables with respect to the symplectic form on the time–frequency domain: from the point of view of the linear canonical transformation, the ...

  3. Multitaper - Wikipedia

    en.wikipedia.org/wiki/Multitaper

    The multitaper method overcomes some of the limitations of non-parametric Fourier analysis. When applying the Fourier transform to extract spectral information from a signal, we assume that each Fourier coefficient is a reliable representation of the amplitude and relative phase of the corresponding component frequency. This assumption, however ...

  4. Rectangular mask short-time Fourier transform - Wikipedia

    en.wikipedia.org/wiki/Rectangular_mask_short...

    In mathematics and Fourier analysis, a rectangular mask short-time Fourier transform (rec-STFT) has the simple form of short-time Fourier transform. Other types of the STFT may require more computation time than the rec-STFT. The rectangular mask function can be defined for some bound (B) over time (t) as

  5. Fejér kernel - Wikipedia

    en.wikipedia.org/wiki/Fejér_kernel

    In mathematics, the Fejér kernel is a summability kernel used to express the effect of Cesàro summation on Fourier series. It is a non-negative kernel, giving rise to an approximate identity . It is named after the Hungarian mathematician Lipót Fejér (1880–1959).

  6. Harmonic analysis - Wikipedia

    en.wikipedia.org/wiki/Harmonic_analysis

    Harmonic analysis is a branch of mathematics concerned with investigating the connections between a function and its representation in frequency.The frequency representation is found by using the Fourier transform for functions on unbounded domains such as the full real line or by Fourier series for functions on bounded domains, especially periodic functions on finite intervals.

  7. Spectral method - Wikipedia

    en.wikipedia.org/wiki/Spectral_method

    Compute the Fourier transform (b j,k) of g.Compute the Fourier transform (a j,k) of f via the formula ().Compute f by taking an inverse Fourier transform of (a j,k).; Since we're only interested in a finite window of frequencies (of size n, say) this can be done using a fast Fourier transform algorithm.

  8. Multidimensional transform - Wikipedia

    en.wikipedia.org/wiki/Multidimensional_transform

    An example of a weakly nonlinear circuit. The inverse multidimensional Laplace transform can be applied to simulate nonlinear circuits. This is done so by formulating a circuit as a state-space and expanding the Inverse Laplace Transform based on Laguerre function expansion.

  9. Fourier shell correlation - Wikipedia

    en.wikipedia.org/wiki/Fourier_shell_correlation

    Typically, random halves are used, although some programs may use the even particle images for one half and the odd particles for the other half of the data set. Some publications quote the FSC 0.5 resolution cutoff, which refers to when the correlation coefficient of the Fourier shells is equal to 0.5.