Re: numerical integration
- To: mathgroup at smc.vnet.net
- Subject: [mg110639] Re: numerical integration
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Wed, 30 Jun 2010 01:49:12 -0400 (EDT)
On 6/29/10 at 8:39 AM, ofershl at gmail.com (ofer) wrote: >thanks peter. actually i don't get error messages but warnings like >: >NIntegrate::slwcon: Numerical integration converging too slowly; \ >suspect one of the following: singularity, value of the integration >\ is 0, highly oscillatory integrand, or WorkingPrecision too small So, try increasing WorkingPrecision or trying a different method or both. No matter what is chosen for the default settings of a numerical integration routine, they will never be adequate for all possible integrals. NIntegrate allows for quite a bit of customization in terms of precision, accuracy and methods used to perform the integration. >and the result i get is far from the accurate result obtained via >analytic methods Well the error message is stating there is a problem with convergence. So, why would you expect the result to be accurate with that error message? And if you have an accurate result obtained by analytic methods, why bother with NIntegrate any further? Doing integration problems is hard. It should never be surprising that the built-in routines with default settings fail for some integrals.