AW: Re: Integrate returns 0
- To: mathgroup at smc.vnet.net
- Subject: [mg23948] AW: [mg23935] Re: Integrate returns 0
- From: Klamser at t-online.de (Peter Klamser)
- Date: Sun, 18 Jun 2000 03:00:34 -0400 (EDT)
- Disposition-notification-to: "Peter Klamser" <klamser@t-online.de>
- Sender: owner-wri-mathgroup at wolfram.com
Hi, Jens-Peer Kuska [kuska at informatik.uni-leipzig.de] wrote on a similar question: Hi, you *must* triangulate irregular data. If it is too slow you should look on Tom Wickham-Jones packages -- there is a Delaunay triangulation in a C program that much faster than the pure Mathematica version http://www.mathsource.com/Content/Enhancements/Graphics/3D/0208-976 Regards, Peter Klamser -----Ursprüngliche Nachricht----- Von: Jens-Peer Kuska [mailto:kuska at informatik.uni-leipzig.de] Gesendet: Freitag, 16. Juni 2000 06:57 An: mathgroup at smc.vnet.net Betreff: [mg23935] Re: Integrate returns 0 Hi, a bug the integral is never zero. Regards Jens "Felix E. Klee" wrote: > > Hi, > > when I define the function > f[x_,n_]:=D[Exp[-x^2],{x,n}]^2 > and execute > Integrate[f[x,n],{x,-Infinity,Infinity}] > the result is > 0 > > However this is not correct for all parameters n since > Integrate[f[x,1],{x,-Infinity,Infinity}] > returns > Sqrt[Pi/2] > > Is this a bug in Mathematica or am I doing something wrong? > > TIA, > > Felix