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Re: how to define right function for minimization

 From: address@hidden Subject: Re: how to define right function for minimization Date: Sun, 11 Feb 2007 13:22:25 -0800 (PST)

```your output of "f(a, x) " says you already do wrong, x must be 1st in
minimization solvers
one of solutions: try for example
fun1 = @(x,param) (param*x-1)^2;
a=2;
[x fv] = fmins(@(x) fun1(x,a) ,0);
in matlab it works but in my octave 2.9.9 as far as I remember - not, you
should use direct substitution of a=2 or globals.
for smooth funcs fminunc is better, for nonsmooth - my ralg() or
ominsearch() is better than fmins (at least at those task I dealt with)
WBR, Dmitrey

ontogenez wrote:
>
> i tried to use a constant for function minimization. i coded:
>
> a=2
> fun1=inline('(a*x-1)^2')
> fmins(fun1,0)
>
> octave gives me
> a = 2
> fun1 =
>
> f(a, x) = (a*x-1)^2
>
> error: `x' undefined near line 2 column 12
> error: evaluating binary operator `*' near line 2, column 11
> error: evaluating binary operator `-' near line 2, column 13
> error: evaluating binary operator `^' near line 2, column 16
> error: called from `?unknown?'
> error: evaluating binary operator `*' near line 63, column 12
> error: evaluating assignment expression near line 63, column 6
> error: called from `nmsmax' in file
> `/usr/share/octave/site/m/octave-forge/optim/nmsmax.m'
> error: evaluating assignment expression near line 78, column 9
> error: called from `fmins' in file
> `/usr/share/octave/site/m/octave-forge/optim/fmins.m'
> error: near line 3 of file `/usr/share/octave/site/m/minimization.m'
>
> how can i define function with a=2?
>
>

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