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From: roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson)
Newsgroups: comp.soft-sys.matlab
Subject: Re: Find Minimum
Date: Mon, 11 Feb 2008 17:03:57 +0000 (UTC)
Organization: National Research Council Canada - Conseil national de rechereches Canada
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In article <Xns9A41778E37573scottseidmanmindspri@130.133.1.4>,
Scott Seidman  <namdiesttocs@mindspring.com> wrote:
>roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) wrote in news:fopten$3j$1
>@canopus.cc.umanitoba.ca:

>> No you cannot. Although you have a limited number of B and C to try,
>> you have an infinite number of A to try. 

>That's like saying that there's no solution for any unconstrained 
>optimization problem, no?

No, it isn't. Unconstrained is not the same as not knowing anything
about the function.

>People do this every day.

>Yes, there's a way to solve it,

What way would that be? Recalling that the function in this case
is a "black box" that we are not permitted to examine and which has
an unknown complexity. For example, the original poster's MyFun(A,B,C)
could turn out to be an expression of a conjecture of a particular
set of zeros of the Zeta function, and knowing the minimum of the
function without having to evaluate all of infinity would prove
(or disprove) the conjecture.

>In general, the answer to "can matlab do this"-type problems is that if you 
>can do it in any programming language, you can do it in matlab.

To my mind, you have not established that the unconstrained minima
of arbitrary black-box functions can be found in finite time in *any*
programming language.
-- 
   "I was very young in those days, but I was also rather dim."
   -- Christopher Priest