Inv.Interpol.Function

*To*: mathgroup at smc.vnet.net*Subject*: [mg36663] Inv.Interpol.Function*From*: martinskogstad at hotmail.com (martin skogstad)*Date*: Wed, 18 Sep 2002 02:09:44 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Dear NG Mabye this is too simple, but I cant just figure it out I want to get an inverse function for y[t] where y[t_]:=NIntegrate[R[x]^4,{x,0,t}] /. ndsolution[[1]] and R[t] is an interpolatingfunction(R>0 from NDSolve) on the interval 0=<t=<T after that I hope to be able to calculate the integral : a = (1/y[T])* NIntegrate[R[InvFunction[y[t]]*Cos[y[t]], {y[t], 0, y[T]}] it works with a constant instead of R[t]. Hope you can help, and that the above is understandable. Martin Skogstad