Re: Problems integrating InterpolatingFunction

*To*: mathgroup at smc.vnet.net*Subject*: [mg116049] Re: Problems integrating InterpolatingFunction*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Sun, 30 Jan 2011 03:32:35 -0500 (EST)

You must use NIntegrate s = y /. NDSolve[{y'[x] == y[x] Cos[x + y[x]], y[0] == 1}, y, {x, 0, 30}][[1]]; NIntegrate[1/s[x]^2, {x, 0, 30}] 10325.5 Bob Hanlon ---- Sergio Miguel Terrazas Porras <sterraza at uacj.mx> wrote: ============= Hello group, I use NDSolve for a nonlinear differential equation, and I get an InterpolatingFunction, as expected. I can plot it, evaluate it, etc. The problem I have is that now I need to integrate 1/(the square of the InterpolatingFunction), and I get nothing but the input back. Any ideas? Thanks in advance. Sergio Terrazas