Re: a problem about NDSolve and NIntegrate

*To*: mathgroup at smc.vnet.net*Subject*: [mg80021] Re: a problem about NDSolve and NIntegrate*From*: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>*Date*: Fri, 10 Aug 2007 06:45:11 -0400 (EDT)*Organization*: The Open University, Milton Keynes, UK*References*: <f9emog$lpq$1@smc.vnet.net>

lynn wrote: > I'm tring to solve a diffrential equation with > > its upper boundary as a variable. > > and then I want to integrate it, and define > > it as a funcion with two variable. > > However, I don't know why it doesn't work at the second step. > > > my equation is as following, > > f[c_?NumberQ]:=y[x]/.NDSolve[{eqn,y[0]==1,y'[0]==0},y,{x,0,c},MaxSteps- >> 10000][[1]] > > n[w_NumberQ,c_NumberQ]:=NIntegrate[c*y[x]*(r-w)],{r,w,1}] ------^(1)------^(1)-----------------------------^(2) 1. To apply a test function (predicate) to a pattern, you must use an question mark '?' (as you did when defining f). 2. Extraneous square bracket. A /syntacticly/ correct code is n[w_?NumberQ, c_?NumberQ] := NIntegrate[c*y[x]*(r - w), {r, w, 1}] <snip> -- Jean-Marc