Hallo,
I am investigating the JUniForm module of JAG3D, specifically the ellipse fitting function. Without more detailed descriptions I cannot understand the equation given under Properties > Feature. What approach/equation is the least square fit of an ellipse based on? Can you refer me to any relevant literature?
I would very much appreciate if you took the time to read and answer my question.
Thank you,
Antonio
by Micha 
, Bad Vilbel, Monday, July 12, 2021, 01:20 (1228 days ago) @ a2pac
Hello Antonio,
What approach/equation is the least square fit of an ellipse based on? Can you refer me to any relevant literature?
Using 2D or 3D data?
Kind regards
Micha
--
applied-geodesy.org - OpenSource Least-Squares Adjustment Software for Geodetic Sciences
Using 2D data.
Kindly,
Antonio
by Micha , Bad Vilbel, Monday, July 12, 2021, 03:14 (1228 days ago) @ a2pac
Hello,
the equation is given by
$\sum_{j=1}^2 s_j = 2a$
where
$s_j = |P_i - F_j|$
is the distance between the i-th point and the j-th focal point. Parameter a denotes the major semi-axis.
This model is also valid for the spatial case, cf. Lösler, M. and Nitschke, M., 2010. Bestimmung der Parameter einer Regressionsellipse in allgemeiner Raumlage. Allgemeine Vermessungs-Nachrichten, Vol. 117(3), pp. 113-117
and can be used to parametrize an elliptical cylinder, cf. Lösler, M. 2020. Modellierung und Bestimmung eines elliptischen Zylinders. Allgemeine Vermessungs-Nachrichten, Vol. 127(2), pp. 87-93
Kind regards
Micha
--
applied-geodesy.org - OpenSource Least-Squares Adjustment Software for Geodetic Sciences
Micha,
the attached literature gives me all the answers.
Thank you for your help and responsiveness. 
Antonio