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meaning of numpy.fft coefficients

 
 
Joey
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      07-09-2011
the list generated by numpy is of form [ a+bi, c+di, ...]

could anybody tell me the meaning of the coefficients a and b? I am
very confused about fourier transform!

information provided by numpy reference says Ak = Sum of a[m] *
exp{-2*pi * i * m * k / n} for m from 0 to n-1

Which part is a and which part is b and what is the meaning of each
part?

Thx in adv.
 
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Corey Richardson
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      07-09-2011
Excerpts from Joey's message of Fri Jul 08 20:14:29 -0400 2011:
> the list generated by numpy is of form [ a+bi, c+di, ...]
>
> could anybody tell me the meaning of the coefficients a and b? I am
> very confused about fourier transform!
>


a+bi is a typical complex number. a is the real part, b is the imaginary.
Python uses j,

>>> 4+5j

(4+5j)

http://en.wikipedia.org/wiki/Complex_number
http://docs.python.org/library/stdty...l#typesnumeric
--
Corey Richardson
"Those who deny freedom to others, deserve it not for themselves"
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