Integrating an InterpolatingFunction times another function

*To*: mathgroup at smc.vnet.net*Subject*: [mg126047] Integrating an InterpolatingFunction times another function*From*: Andrew DeYoung <adeyoung at andrew.cmu.edu>*Date*: Fri, 13 Apr 2012 04:57:11 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com

Hi, I have made a sample InterpolatingFunction: points = {{0, 0}, {1, 1}, {2, 3}, {3, 4}, {4, 3}, {5, 0}}; ifun = Interpolation[points] The following integral computes fine: Integrate[ifun[x], {x, 1, 5}] However, this integral will not be evaluated: Integrate[x*ifun[x], {x, 1, 5}] Why will this integral not be computed? Is there any way that I can compute this integral? Thank you kindly! Andrew DeYoung Carnegie Mellon University

**Follow-Ups**:**Re: Integrating an InterpolatingFunction times another function***From:*Bob Hanlon <hanlonr357@gmail.com>