Re: Problem with the zero-term of Fourier[]
- To: mathgroup at smc.vnet.net
- Subject: [mg19642] Re: Problem with the zero-term of Fourier[]
- From: hans.steffani at e-technik.tu-chemnitz.de (Hans Steffani)
- Date: Tue, 7 Sep 1999 00:28:37 -0400
- Organization: Chemnitz University of Technology, GER
- References: <7qsftj$17c@smc.vnet.net> <7qvu1p$4o2@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Paul Abbott <paul at physics.uwa.edu.au> writes: >Hans Steffani wrote: >> If have a long list of measured values in ixr. >> (Plus@@ixr)/Sqrt[Length[ixr]] >> gives >> -146.263 >> >> but >> Fourier[ixr][[1]] >> gives >> -56.1317-3.03437 I >> >> which is complex although it should be real (ixr is a list of >> real numbers) and it is different from the first term althugh >> it should be the same. >Assuming that ixr is real then I can only guess that the problem >arises from the bug with packed arrays of complex numbers? Sorry, what do you mean with "packed arrays of complex number"? I'm am sorry that I do not have a simple example; maybe you want analyze me measuered data , but I am not sure about ;) h.f.s. -- Hans Friedrich Steffani Institut fuer Elektrische Maschinen und Antriebe, TU Chemnitz mailto:hans.steffani at e-technik.tu-chemnitz.de http://www.tu-chemnitz.de/~hfst/