Re: Bug in FourierTransform?
- To: mathgroup at smc.vnet.net
- Subject: [mg31088] Re: Bug in FourierTransform?
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Tue, 9 Oct 2001 01:55:39 -0400 (EDT)
- Organization: Universitaet Leipzig
- References: <9pme6e$657$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi, FourierTransform[] does not split sums into single terms. Because FourierTransform[a+b,_,_] may extist but FourierTransform[a,_,_]+FourierTransform[b,_,_] may be not existing or may be divergent. I assume that Mathematica try to integrate the full expression and this take a very long time. Regards Jens Daniel Arteaga wrote: > > Hi, > > Mathematica hangs up when trying to compute the Fourier transform of > > F[X_, Y_] := > E^(-100 + 20*X - 2*X^2 - 10*Y - Y^2/2) + > E^(-100 - 2*X^2 - 10*Y - Y^2/2 + 10*(10 + Y)) + > E^(-200 + 20*X - 2*X^2 - 10*Y - Y^2/2 + 10*(2*X + Y)) + > E^(-200 - 2*X^2 - 10*Y - Y^2/2 + 10*(10 + Y) + 10*(2*X + Y)) > > FourierTransform[F[X,Y],Y,P] > > (keeps running forever) > > However, it computes very fast the Fourier transform of each term > separately. I am using Mathematica 4.1 in Windows 2000. Mathematica 2.2 > computed correctly this fourier transform. > > Any idea? > > Daniel Arteaga