       Re: a problem about NDSolve and NIntegrate

• To: mathgroup at smc.vnet.net
• Subject: [mg80001] Re: a problem about NDSolve and NIntegrate
• From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
• Date: Fri, 10 Aug 2007 01:54:21 -0400 (EDT)
• Organization: Uni Leipzig
• References: <f9emog\$lpq\$1@smc.vnet.net>

```Hi,

a) you mean f[c_?NumericQ] :=... and NumberQ because NumberQ is a test
and you need ? in the pattern to apply the test.
b) in you n[] function you use y[x] but only f[c] return
something that include y[x] -- how shall n[] find aut that
it need to compute f[c] to get y[] ??

Regards
Jens

lynn wrote:
> Hello,
>
> 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==1,y'==0},y,{x,0,c},MaxSteps-
>> 10000][]
>
> n[w_NumberQ,c_NumberQ]:=NIntegrate[c*y[x]*(r-w)],{r,w,1}]
>
> function f works well, however there's some problem in funcion n,
>
> and it's confused me for a long time...,
>