Azzurra,
Two other methods to try are:
Point on surface
Pole of inaccessibility
Both found in the Processing Toolbox
David
On 1/12/2021 2:13 PM, Brent Wood wrote:
This may be a suitable approach, not specifically the ellipse axis
approach, but:
Vector -> Geometry tools -> Centroid
may do what you want, depending on exactly how QGIS calculates the
centroid...
Brent Wood
Principal Technician, Fisheries
NIWA
DDI: +64 (4) 3860529
------------------------------------------------------------------------
*From:* Qgis-user <qgis-user-boun...@lists.osgeo.org> on behalf of
Azzurra Lentini <azzurralent...@gmail.com>
*Sent:* Wednesday, January 13, 2021 08:04
*To:* qgis-user <qgis-user@lists.osgeo.org>
*Subject:* [Qgis-user] how to find center of polygons and/or major and
minor diameters
Hi to all, any suggestion on how to quickly draw the minor and major
diameters of different polygons? I have a shapefile of polygons: some
of the polygons are ellipses and others are similar to ellipses but
not regular.
My aim is to find the center of these polygons (In this aim I was
thinking to draw the 2 diameters and to use the intersection of these
diameters as a center point of the polygon)
Thanks, Azzurra
--
Lecturer GIS University "Roma Tre"
Consultant Environmental Risk Prevention and Hydrogeology
AZZURRA LENTINI
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*Par respect pour l'environnement,*
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<https://www.niwa.co.nz> Brent Wood
Principal Technician - GIS and Spatial Data Management
Programme Leader - Environmental Information Delivery
+64-4-386-0529 |
National Institute of Water & Atmospheric Research Ltd (NIWA)
301 Evans Bay Parade Hataitai Wellington New Zealand
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