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From: =?windows-1252?Q?Hans-Bernhard_Br=F6ker?= <HBBroeker@t-online.de>
Newsgroups: comp.graphics.apps.gnuplot
Subject: Re: Fit 3D Line to data
Date: Wed, 25 Feb 2015 19:25:40 +0100
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Xref: csiph.com comp.graphics.apps.gnuplot:2789

Am 25.02.2015 um 14:34 schrieb Karl:
> Am 24.02.2015 um 20:16 schrieb Hans-Bernhard Bröker:
>> Am 23.02.2015 um 07:27 schrieb Erik Zweigle:
>>> I am trying to fit a line to the 4 data points shown below.

>> That's not a well-defined task, I'm afraid.  Fitting a line to a dataset
>> is reasonably well-defined in 2D, but not in 3D.

> Hm. I´d say you define the line with parameters x0,y0,z0 and two angles,
> derive the minimum distance d(x,y,z) of a point xyz from that line, and
> minimise that.

While that's _one_ viable interpretation of the stated problem, it's far 
from being the only one.  Which is precisely what makes the task  not 
well-defined.