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Re: bug in IDL's hanning() window-generating function

FYI: the hanning() routine that I have from matlab (ver 1.4, 1994) is in
worse shape than the one provided with IDL. It is symmetric (not
fft-symmetric) and it does not even taper to zero.


Paul van Delst wrote:

> bennetsc@NOSPAMucs.orst.edu wrote:
> >
> > In article <MPG.15d1a1e0a012bdcd989e44@news.frii.com>,
> > David Fanning <david@dfanning.com> wrote:
> > >Scott Bennett writes after a long analysis of the Hanning function:
> > >
> > >>      In any case, I think the point Harris made is that a discrete
> > >> sampling of a window function should not taper to the same value at
> > >> the end that it has at the beginning because to do so would include
> > >> the first sample of the *next* period (windowed segment.)  So IDL's
> > >> hanning() gets it wrong for both even- and odd-length windows. :-(
> > >
> > >Uh, huh. And how did RSI respond when you contacted them
> > >about it?
> > >
> >      I didn't contact them.  I'm disgusted with them after seeing how
> > they cheated my faculty advisor and, when I asked them to rectify
> > their errors, they refused to do so.  I recommended to my advisor that
> > he turn the whole matter over to the university's legal counsel.  He
> > told me that he was not going to renew the service contract any more,
> > so I doubt he will bother with having the legal counsel deal with it,
> > but either way it will be his decision and it's now out of my hands.
> > Given their denial of service while we had a service contract, I doubt
> > they would do any better now that we no longer have a service contract.
> Oi vey. another future matlab user.... ?  :o)
> --
> Paul van Delst           A little learning is a dangerous thing;
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