Re: problem with integrating an interpolated list
- To: mathgroup at smc.vnet.net
- Subject: [mg103018] Re: problem with integrating an interpolated list
- From: Harutyun Amirjanyan <amirjanyan at gmail.com>
- Date: Thu, 3 Sep 2009 19:57:55 -0400 (EDT)
- References: <h7b04r$d8$1@smc.vnet.net> <h7o85i$nht$1@smc.vnet.net>
Hi Tobias, I guess I'm late with this post, so wouldn't write any code. contact me if you need more help. InterpolatingFunction does a Piecewise polynomial interpolation so Integrate does a symbolical integration over each piece. however if variable transformations are used Integrate can't recognize InterpolatingFunction object. In this case you can make transformation on data and then construct interpolating function. With NIntegrate, the nonsmooth behavior of InterpolatingFunction near the boundaries of pieces produces an error message and requires many recursive steps to evaluate accurately. before v6 there was a special function to deal with this (NIntegrateInterpolatingFunction in FunctionApproximations) but now NIntegrate does the job. In your case it doesn't work because your data is really unsmooth. thanks for making "Complete Code for trying at home" it was very convenient