Timeline for Calculating dominant angle of a polygon in QGIS without main_angle function
Current License: CC BY-SA 4.0
20 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 9, 2021 at 3:00 | history | tweeted | twitter.com/StackGIS/status/1358974110488031234 | ||
| Jan 23, 2021 at 15:17 | comment | added | Zoltan | Here is a Python example for PCA: github.com/OSGeoLabBp/tutorials/blob/master/english/… | |
| Jan 23, 2021 at 14:38 | history | edited | HansrajR | CC BY-SA 4.0 | added 238 characters in body |
| Jan 23, 2021 at 14:35 | comment | added | HansrajR | @Zoltan I used XLSTAT to use Principal Component Analysis but did not achieve conculsive results. Computed results and report is accessible from following link: drive.google.com/drive/folders/… | |
| Jan 15, 2021 at 11:52 | history | edited | Kadir Şahbaz | CC BY-SA 4.0 | added 3 characters in body; edited title |
| Jan 15, 2021 at 11:27 | answer | added | Babel | timeline score: 3 | |
| Jan 15, 2021 at 10:52 | comment | added | HansrajR | @MrXsquared I tried to add the expressions but could not get it right | |
| Jan 15, 2021 at 10:51 | history | edited | HansrajR | CC BY-SA 4.0 | added 304 characters in body |
| Jan 15, 2021 at 10:36 | history | edited | HansrajR | CC BY-SA 4.0 | added 287 characters in body |
| Jan 15, 2021 at 9:32 | comment | added | HansrajR | @Zoltan I successfully installed FactoQGIS a GUI tool based on an R script to perform Geometric Data Analysis in a Free and Open Source GIS available from the following link:github.com/ESO-Rennes/FactoQGIS The image in the following link is the interface: i.sstatic.net/qZmNR.pngCould you advise on the parameters to set | |
| Jan 15, 2021 at 8:27 | comment | added | HansrajR | Is there an alternative I am not conversant with Scikit-learn. I found Line Direction Histogram QGIS plugin, it produced a Rose diagram as in the following image: i.sstatic.net/UbGyi.png but does not provide a numerical value. | |
| Jan 15, 2021 at 8:16 | comment | added | Zoltan | The first eigenvector gives the direction of the first principal direction. See: scikit-learn.org/stable/auto_examples/cross_decomposition/… | |
| Jan 15, 2021 at 7:50 | comment | added | HansrajR | @Zoltan The final results I am seeking is the average main angle of orientation of the polygons collectively which visually approximates to 30 degrees. | |
| Jan 15, 2021 at 7:38 | comment | added | Zoltan | You may use principal component analysis (PCA). Scikit-learn Python package has a PCA function. See: doc.ic.ac.uk/~dfg/ProbabilisticInference/old_IDAPILecture14.pdf | |
| Jan 15, 2021 at 6:27 | history | edited | HansrajR | CC BY-SA 4.0 | added 254 characters in body |
| Jan 15, 2021 at 5:01 | history | edited | HansrajR | CC BY-SA 4.0 | added 124 characters in body |
| Jan 15, 2021 at 4:50 | history | edited | HansrajR | CC BY-SA 4.0 | added 1107 characters in body |
| Jan 14, 2021 at 18:16 | comment | added | HansrajR | The folder contains shapefile of the polygons. In the attribute table, the main_angle field is calculated using main_angle function in QGIS 3.16. The line is drawn using centroid of each polygon and the main angle. main_angle Returns the main angle of a geometry (clockwise, in degrees from North), which represents the angle of the oriented minimal bounding rectangle which completely covers the geometry | |
| Jan 14, 2021 at 18:08 | comment | added | bugmenot123 | Which polygon in that file is it? And how did you create those lines? | |
| Jan 14, 2021 at 17:29 | history | asked | HansrajR | CC BY-SA 4.0 |