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On the diagonalization of the discrete Fourier transform

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 نشر من قبل Shamgar Gurevich
 تاريخ النشر 2008
  مجال البحث الهندسة المعلوماتية
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 تأليف Shamgar Gurevich




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The discrete Fourier transform (DFT) is an important operator which acts on the Hilbert space of complex valued functions on the ring Z/NZ. In the case where N=p is an odd prime number, we exhibit a canonical basis of eigenvectors for the DFT. The transition matrix from the standard basis to the canonical basis defines a novel transform which we call the discrete oscillator transform (DOT for short). Finally, we describe a fast algorithm for computing the discrete oscillator transform in certain cases.



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