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  1. #1
    Registered User TheRipper's Avatar
    Join Date: Jul:2005
    Location: Germany/Bulgaria
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    , fft. , ....

    Python Numpy:

    >>>fft([1])
    array([ 1.+0.j ])

    >>>fft([1, 1])
    array([ 2.+0.j, 0.+0.j ])

    >>>fft([1, 2])
    array([ 3.+0.j, -1.+0.j ])

    >>>fft([1, 2, 2, 5])
    array([ 10.+0.j, -1.+3.j, -4.+0.j, -1.-3.j ])

  2. #2
    Registered User
    Join Date: Oct:2003
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    http://en.wikipedia.org/wiki/Discret...orm#Definition :
    "Definition
    The sequence of N complex numbers x0, ..., xN−1 is transformed into another sequence of N complex numbers according to the DFT formula:"

  3. #3
    Registered User
    Join Date: Jan:2005
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    ? FFT ... ... , ?
    , , ... ...

  4. #4
    Registered User TheRipper's Avatar
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    , . .

  5. #5
    Registered User
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    , 4 , ,
    (. http://docs.scipy.org/doc/numpy/refe...#numpy.fft.fft , - )
    ( ) - - - , fft .
    , , ... ...

  6. #6
    Undead user Oldman's Avatar
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    FFT (time domain) (frequency domain). , . = index*sampleRate/FFTPoints, sqrt(re*re+im*im), atan(im/re).
    rfft.
    .

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