# Re: Oscillating method of integration

From: <andreyk1_at_post.tau.ac.il>
Date: Fri, 25 Aug 2006 13:49:39 +0300

Dear Lorenzo,

Thanks for solution, but this is not my case. The integral is too complicated to be done analitically. The only way is numerical calculation. Actually I can integrate between BesselJ zeroes and sum up these intervals, but it is not efficient.

Andrew.

Quoting Lorenzo Moneta <Lorenzo.Moneta_at_cern.ch>:

> Hi Andrew,
>
> I don't know of a method for 2d with oscillatory function.
> Hower, you should be able for a Bessel of order 0 to solve the
> integral analytically,
> using the Bessel J0 definition
>
> see http://en.wikipedia.org/wiki/Bessel_function
>
> Cheers,
>
> Lorenzo
> On 24 Aug 2006, at 12:14, andreyk1_at_post.tau.ac.il wrote:
>
> >
> >
> > Dear rooters,
> >
> > I need to integrate over two dimensionl oscillating function
> > (TMath::BesselJ(0,x*y), 0<x<inf, 0<y<inf). I use TF1 with
> > IntegralMultiple, but
> > the answer is not stable, a change in max_points leads to a
> > different result. I
> > tried to increas the number of max_points to 1e+6 but the result is
> > still
> > unstable. Is there some method of integrating over oscillating
> > function with
> > arbitry dimensions? (in my case it is dim = 2).
> >
> >
> > Thanks a lot!
> >
> >
> > Andrew
> >
> > ----------------------------------------------------------------
> > This message was sent using IMP, the Internet Messaging Program.
> >
> >
>
>
> +++++++++++++++++++++++++++++++++++++++++++
> This Mail Was Scanned By Mail-seCure System
> at the Tel-Aviv University CC.
>

This message was sent using IMP, the Internet Messaging Program. Received on Fri Aug 25 2006 - 12:50:13 MEST

This archive was generated by hypermail 2.2.0 : Mon Jan 01 2007 - 16:32:00 MET