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From: "Vahila Chowdary " <k.vahila@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: How are the values for h taken in Hilbert transformation?
Date: Wed, 4 Nov 2009 13:53:02 +0000 (UTC)
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Helllo everybody!

I would like to know the way 'h' in hilbert transformation is given values. This is the thing i found in MATLAB  but really could nt understand how they do it.

In detail, hilbert uses a four-step algorithm:

   1.It calculates the FFT of the input sequence, storing the result in a vector x.
   2.It creates a vector h whose elements h(i) have the values:
          * 1 for i = 1, (n/2)+1
          * 2 for i = 2, 3, ... , (n/2)
          * 0 for i = (n/2)+2, ... , n
   3.It calculates the element-wise product of x and h.
   4.It calculates the inverse FFT of the sequence obtained in step 3 and returns the first n elements of the result.

Could someone tell me the 2nd step clearly?

Thank you