Alpha Shapes algorithm with new cumulative parameter for gradually changes from concave hull to convex hull.
Two implementations are represented. One of them on python 3
and another one on cython
.
To execute algorithm run alfa_example.py
.
You can find example dataset in folder data
and some analitics pictures in folder analysis
.
The example dataset is part of Petrogradsky district, Saint Petersburg, Russia by Open Street Map
. There are 3922 points in the dataset.
Algorithm demonstrates gradually changing from concave hull to convex hull:
Time estimation for datasets with different counts of points shows good performs. For comparison, the implementation of the QGIS
for the biggest of these datasets was performed for ~90 minutes.
And additionally hull smoothing was implemented for better demonstration geospatial results: