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From: "John D'Errico" <woodchips@rochester.rr.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Fit quadratic polynomial and find minimum value and its site??
Date: Fri, 16 May 2008 09:36:01 +0000 (UTC)
Organization: John D'Errico (1-3LEW5R)
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"Rajesh Acharya" <rv_acharya@yahoo.com> wrote in message 
<g0j516$dnh$1@fred.mathworks.com>...
> John D'Errico
> I think i was not clear... initially i tried to fit a 
> quadratic polynomial but didnot find any direct function in 
> matlab to find the minimum value of the polynomial thus 
> whether we have such a function in matlab was my first 
> question...

And my point was, that a quadratic
function is trivial to find the minimum of.
Use what you know about mathematics
to solve the trivial problems.

Its not even worth looking for fminbnd,
which would do what you wanted, or
fminsearch, another tool which would
have done it.


> then i tried to fit a spline(cubic curve) to the same data 
> because i found a function 'fnmin' which gives me the 
> minimum val and its site if i give a spline as input... 
> that was the second part of the mail (both mutually 
> exclusive events)
> however in this second part i think i made some mistake in 
> the syntax and therefore got wrong results and i wanted 
> some help on the systax.... 

Ok, then why not show us what you tried
that failed, instead of fishing around for
someone to give you the answer? fnmin
is perhaps the most trivial function to use
I've ever seen, so show us what you did.

John