Re: Re: Re: Re: Finding the Fourier transform of discrete functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg52685] Re: [mg52662] Re: Re: Re: Finding the Fourier transform of discrete functions*From*: DrBob <drbob at bigfoot.com>*Date*: Thu, 9 Dec 2004 20:22:40 -0500 (EST)*References*: <cohi1d$1fh$1@smc.vnet.net> <200412011057.FAA19902@smc.vnet.net> <comgk7$7a2$1@smc.vnet.net> <200412030853.DAA26040@smc.vnet.net> <cos159$dl7$1@smc.vnet.net> <200412070909.EAA09224@smc.vnet.net>*Reply-to*: drbob at bigfoot.com*Sender*: owner-wri-mathgroup at wolfram.com

>> description "discrete" apply not to a symbolic expressions. Maybe not, but it does apply to mathematical functions and their domains. See for instance: http://www.2dcurves.com/discrete/discrete.html http://caltechcdstr.library.caltech.edu/5/ http://www.sparknotes.com/math/algebra2/discretefunctions/terms/term_B.2.html http://portal.acm.org/citation.cfm?id=225072 http://mathforum.org/epigone/sci.math.research/grorrinroi http://www.informs.org/Conf/NewOrleans95/TALKS/MC26.1.html http://www.ds.unifi.it/VL/VL_EN/dist/dist1.html (I could go on all day.) Bobby On Tue, 7 Dec 2004 04:09:59 -0500 (EST), Jens-Peer Kuska <kuska at informatik.uni-leipzig.de> wrote: > Hi, > > I think x_Integer is a pattern, that stand for any integer number, > it is a symbolic expression and the description "discrete" apply > not to a symbolic expressions. > > Regards > Jens > > "DrBob" <drbob at bigfoot.com> schrieb im Newsbeitrag > news:cos159$dl7$1 at smc.vnet.net... >> No, I think x_Integer is discrete. >> >> Obviously. >> >> Bobby >> >> On Fri, 3 Dec 2004 03:53:37 -0500 (EST), Jens-Peer Kuska >> <kuska at informatik.uni-leipzig.de> wrote: >> >>> Hi, >>> >>> and you think that 1<=x<12 is discret, and not a infinite number >>> of continuous values ?? Strange ! >>> >>> Regards >>> Jens >>> >>> "DrBob" <drbob at bigfoot.com> schrieb im Newsbeitrag >>> news:comgk7$7a2$1 at smc.vnet.net... >>>>>> what is a "discrete function". >>>>>> if it is a function, the parameter is continuous and >>>>>> FourierTransform[] >>>>>> compute the transformation. >>>> >>>> A discrete function is a function with a discrete domain. >>>> >>>> For instance, this is a discrete function on the obvious domain: >>>> >>>> f[x_Integer]/;1<=x<=12 = Sin@x >>>> >>>> It is NOT the Sin function, for the simple reason that the domain of a >>>> function (in math or mathematica) is part of its definition. >>>> >>>> Bobby >>>> >>>> On Wed, 1 Dec 2004 05:57:38 -0500 (EST), Jens-Peer Kuska >>>> <kuska at informatik.uni-leipzig.de> wrote: >>>> >>>>> Hi, >>>>> >>>>> what is a "discrete function". If it is discrete you have a array of >>>>> discrete data and Fourier[] compute the DFT of the array, if it is >>>>> a function, the parameter is continuous and FourierTransform[] >>>>> compute the transformation. >>>>> >>>>> Regards >>>>> Jens >>>>> >>>>> >>>>> "Luca" <luca at nospam.it> schrieb im Newsbeitrag >>>>> news:cohi1d$1fh$1 at smc.vnet.net... >>>>>> I found out it's possible to determine the Fourier transform of a >>>>>> function. I tried to look for the discrete fourier transform in the >>>>>> guide, but I can find the item in the list without any explaination of >>>>>> the function. Is it possible to find the Fourier transform of a >>>>>> discrete function? >>>>>> Thanks to everyone. >>>>>> >>>>>> Luca >>>>>> >>>>> >>>>> >>>>> >>>>> >>>>> >>>> >>>> >>>> >>>> -- >>>> DrBob at bigfoot.com >>>> www.eclecticdreams.net >>>> >>> >>> >>> >>> >>> >> >> >> >> -- >> DrBob at bigfoot.com >> www.eclecticdreams.net >> > > > > > -- DrBob at bigfoot.com www.eclecticdreams.net

**References**:**Re: Finding the Fourier transform of discrete functions***From:*"Jens-Peer Kuska" <kuska@informatik.uni-leipzig.de>

**Re: Re: Finding the Fourier transform of discrete functions***From:*"Jens-Peer Kuska" <kuska@informatik.uni-leipzig.de>

**Re: Re: Re: Finding the Fourier transform of discrete functions***From:*"Jens-Peer Kuska" <kuska@informatik.uni-leipzig.de>