Re: Re: Re: help on nonlinear ODEs
- To: mathgroup at smc.vnet.net
- Subject: [mg38686] Re: [mg38664] Re: [mg38648] Re: help on nonlinear ODEs
- From: Selwyn Hollis <selwynh at earthlink.net>
- Date: Sun, 5 Jan 2003 06:33:45 -0500 (EST)
- References: <200301041225.HAA24447@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Jan,
What's wrong is that DSolve simply isn't going to solve a nonlinear
equation like the one you have.
You'll have to use NDSolve---and specific parameter values. Also, you've
got two major difficulties to overcome: (1) the problem is singular at
x=0, where your first BC is specified; and (2) you'll need to do some
kind of shooting method to satisfy the second BC; i.e., solve with
y'[0]==0, y[0]==y0, and find y0 so that y[a]==A6.
What sort of values do you have for A1-A6 and a?
----
Selwyn Hollis
Jan Mangaldan wrote:
> I tried executing your snippet and wound up with an "Unable to fit initial boundary conditions" error.
> What's wrong?
> Jan M. ('_')
>
> P.S. If your interest is only in the numerical evaluation of the DE, I suggest you use NDSolve[] instead.
> Todd Rose <todd.rose at comcast.net> wrote:LC,
>
> Did you mean this?
>
> DSolve[{A1 x^2 y''[x]+A2 x^2 y'[x]^2+A3 x y[x] y[x]==
> A4 x^3 y[x]^4+A5 x^2 y[x]^3,y'[0]==0,y[a]==A6},y[x],x]
>
> Regards,
> Todd
>
> "LC"
> wrote in message
> news:auej2e$538$1 at smc.vnet.net...
>
>>I want to solve the following equation,
>>
>>A1 x^2 y''[x]+A2 x^2 y'[x]^2+A3 x y y[x]=A4 x^3 y^4+A5 x^2 y^3
>>w/BCs:
>>y'[0]=0 and y[a]=A6
>>x is from 0 to a>0
>>
>>Could someone can find a way out for this?
>>
>>Thanks.
>>
>>
>
>
>
>
>
- References:
- Re: Re: help on nonlinear ODEs
- From: Jan Mangaldan <hokenjan@yahoo.com>
- Re: Re: help on nonlinear ODEs