Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2005
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2005

[Date Index] [Thread Index] [Author Index]

Search the Archive

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.
>



  • Prev by Date: Re: Re: Comparison of Mathematica on Various Computers
  • Next by Date: Re: Getting crude approximation to a function
  • Previous by thread: Re: Extract Coefficients of Fourier Series
  • Next by thread: Rodrigues' formula