Re: help on critical points
- To: mathgroup at smc.vnet.net
- Subject: [mg4096] Re: [mg4037] help on critical points
- From: Dennis M Schneider <dschneid at knox.edu>
- Date: Tue, 4 Jun 1996 02:17:38 -0400
- Sender: owner-wri-mathgroup at wolfram.com
On Tue, 28 May 1996, Jose Luis Lugo Goytia wrote:
>
> Could you please give me some advise?
>
> I'm trying to find the critical points of a function
> f:R^n -> R, I do the following:
>
> In[1]:= gradiente[f_,var_]:=Outer[D,{f},var];
>
> In[2]:= ceros[f_,vars_]:= vars /. Solve[Numerator[Together[f]] ==
> Table[0,{i,1,Length[vars]}],vars];
>
> and for example
>
> In[3]:= ceros[gradiente[x^2 y - y^2 -2 x y,{x,y}][[1]],{x,y}] //N
>
> Out[3]= {{1., -0.5}, {0, 0}, {2., 0}}
>
> but if I define the function
>
> In[4]:= PuntosCriticos[f_,vars_]:=
> ceros[gradiente[f @@ vars,vars][[1]],vars] //N;
Remove f @@ and all is well.
Dennis M. Schneider
Department of Mathematics
Knox College
Galesburg, IL 61401
(309) 341 7420
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