Re: NIntegrate singularity problem v4.0 vs v5.0

*To*: mathgroup at smc.vnet.net*Subject*: [mg44482] Re: NIntegrate singularity problem v4.0 vs v5.0*From*: Paul Abbott <paul at physics.uwa.edu.au>*Date*: Wed, 12 Nov 2003 08:01:31 -0500 (EST)*Organization*: The University of Western Australia*References*: <boifkq$od6$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

In article <boifkq$od6$1 at smc.vnet.net>, soummer at stsci.edu (Remi Soummer) wrote: > the following code runs on v4.0.1 but not on v5.0, because of the > changes in NIntegrate function. It seems that v5.0 cannot handle the > conditional definition of the function K[]. > > There is a singularity for r=xi and I tried to use the new option in > v5.0, removing the conditional definition of K[] and giving the > singularity point r=x directly to NIntegrate : There is no need to include a conditional definition. Mathematica's pattern-matcher will correctly handle this. > If someone has ideas about this problem or could help me, I will > greatly appreciate ! See the Notebook at http://physics.uwa.edu.au/pub/Mathematica/MathGroup/SoummerBessel.nb I suspect that many improvements could be made to this code, both in terms of efficiency and elegance. In particular, I suspect that some of the integrals could be performed analytically. Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul