From: "Sanne Christensen" <sc_trold@hotmail.com>
Path: news.mathworks.com!newsfeed-00.mathworks.com!webx
Newsgroups: comp.soft-sys.matlab
Subject: Re: Curve fitting a 3D data set
Message-ID: <eef3579.10@webx.raydaftYaTP>
Date: Fri, 26 Nov 2004 03:59:03 -0500
References: <eef3579.-1@webx.raydaftYaTP> <eef3579.9@webx.raydaftYaTP>
Lines: 36
NNTP-Posting-Host: 130.225.51.45
MIME-Version: 1.0
Content-Type: text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding: 8bit
Xref: news.mathworks.com comp.soft-sys.matlab:244366



Hi Paolo

I've scipped using the lsqcurve with x, y, z - it just wouldn't work
for me. Instead I'm using polyfit (I could also use lsqcurve) on x, y
and x, z respectively so I get two curves in a 2D coordinate system.
Then i project one of the curves onto the other and this way I get my
final curve in a 3D coordinate system. I've heard that there are ways
to do it in 3D in Matlab, but I have a deadline coming up and
therefore I don't have time to figure out how to do it :)

/Sanne

Paolo Benetti wrote:
>
>
> Sanne Christensen wrote:
>>
>>
>> I'm pretty new in the Matlab-world. How do I make curve fitting
> on
>> a
>> 3D data set (x, y, z)? Do I need a special toolbox for it?
>>
>> Thanx for your help :)
>> Sanne
>
> Dear Sanne,
> I think we're working on the same problem.
> I got a set of 3D points in Cartesian coordinates and I want to
> find
> the equation of the paraboloid that describes these points. It
> would
> be an antenna. If I have some interesting news about it I'll tell
> you, hoping you'll do the same!
>
> Paolo