Re: Q
- To: mathgroup at smc.vnet.net
- Subject: [mg41405] Re: [mg41390] Q
- From: Selwyn Hollis <selwynh at earthlink.net>
- Date: Sun, 18 May 2003 05:02:43 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Though there's probably a Mathematica-ally slicker way, the following
will work (and I beg forgiveness for the Do loop!):
n=4;
derivs = Join[{f[t]},
Table[D[F[f[t]],{t,k}], {k,0,n}]]//. {t->0, f[0]->f0};
Do[fk = D[f[t], {t,k}]/. t->0;
derivs = derivs /. fk->derivs[[k+1]], {k,1,n}];
derivs
[reference/plug: A Mathematica Companion for Differential Equations, by
me.]
-----
Selwyn Hollis
http://www.math.armstrong.edu/faculty/hollis
On Saturday, May 17, 2003, at 05:50 AM, Stepan Yakovenko wrote:
> HI!
>
> I've got an equation f'[t]=F[f[t]].
> F[] is known and analytic, (say
> F[x]=x*x). I know f[0]=f0. f0 is
> a number. I want to get all f'[0],
> f''[0], f'''[0], ... assigned
> to their numberical values that can be
> unambiguously found after differentiating
> the source equation as many times as
> needed.
>
>
> --
> Try "win /t" to run Windows in text mode
>
>
>