Re: Extract Coefficients of Fourier Series
- To: mathgroup at smc.vnet.net
- Subject: [mg58865] Re: Extract Coefficients of Fourier Series
- From: "Dana DeLouis" <delouis at bellsouth.net>
- Date: Thu, 21 Jul 2005 03:08:15 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Just for discussion, the function TrigFit has a small bug. It's been around
for awhile, and was not corrected in 5.2.
My default setting for "FourierParameters" is set to something other than
the default of {0,1}. This causes wrong output. With TrigFit, the call to
Fourier does not use "FourierParameters", and makes the assumption that it
is using the Default setting {0,1}.
I recommend editing that file and adding the option "FourierParameters."
Instead of diving by Sqrt[len], and using the default setting, I recommend
just using the Data Analysis setting as below.
Change this line..
fcslist = Fourier[fcslist/Sqrt[len]];
To this.
fcslist = Fourier[fcslist, FourierParameters -> {-1,1}];
HTH
--
Dana DeLouis
Win XP & Office 2003
<mchangun at gmail.com> wrote in message news:dbie2e$brj$1 at smc.vnet.net...
> Hi All,
>
> I have a set of points which have I fitted to a fourier series with
> the TrigFit function. This gives me a fourier series. What I want is
> to extract all the coefficients of the series, square them, then sum
> them. How do I this (more specifically, the extraction step?
>
> Thanks in advanced.
>