Use of the Fast Fourier Transformation

[Daniel Tourde]

Hi !

I would like to know how to use the fft function.

Let's take a simple example :

f(t) = A if -To/2<t<To/2
       0  anywhere else

I can calculate by hand the fourier transformation of this function :

F(nu) = A*To*sin(pi*nu*To)/(pi*nu*To)


However, how can I use fft to compute it ! (Setting A and To with
numerical values of course). I tried to use the fft function but without
great success I should admit.

I would be very grateful if someone could help me to do it.


Thanks in advance

Best regards

                        Daniel Tourde
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Daniel TOURDE                                   E-mail : address@hidden
The Aeronautical Research Institute of Sweden   Tel : +46 8 634 13 44
P.O. Box 11021 S-161 11 BROMMA, Sweden          Fax : +46 8  25 34 81
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