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The two GIS web mapping terms you are describing are indeed clustering and then spatial indexing. Clustering is usually done client side while indexing is done server side, usually using a geodatabase, with a server-side map rendering engine in the middle. In KML, there is a relatively new feature called "Regions" which tries to handle the display side of ...


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You first need to understand the different ways to create geometries and the geometrical relations in GeoDjango (GeoDjango: GEOS API), without a database: 1) create valid geometries: # with Point, Polygon objects of GeoDjango from django.contrib.gis.geos import Point, Polygon, poly = Polygon(((0.0, 0.0), (0.0, 50.0), (50.0, 50.0), (50.0, 0.0), (0.0, ...


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Building on @gene 's answer above if you're looking to approximate a curve as a sequence of points using spline interpolation. In Python you can do this through the scipy.interpolate library. Particularly 1d interpolation. For example import numpy as np import scipy.interpolate coords = np.array([[0, 0], [25, 10], [50, 50]]) #The curve fits as a ...


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Shapely PyQGIS, and GeoDjango use the same API based on the GEOS library: With Shapely: with a list of points: from shapely.geometry import Point, LineString, mapping pt1 = Point(0,0) pt2 = Point(20,20) pt3 = Point (50,50) line = LineString([pt1,pt2,pt3]) #GeoJSON format print mapping(line) {'type': 'LineString', 'coordinates': ((0.0, 0.0), (20.0, ...


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After two years, I'm here to tell you how I did it. It may not be perfect, but it's something. Our cartographic production is limited to some counties inside Brazil. We never update just some part of the graph, but whole cities. So, whenever a city has major cartographic changes, everything is destroyed and replaced. About planarizing the graphs, this is ...


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You can cheat, because the EPSG numbers for UTM zones have a pattern than incorporates the zone number. 269ZZ for UTM north zones, where ZZ is the zone number 327ZZ for UTM south zones, where ZZ is the zone number And, since PostGIS uses the EPSG number for the SRID, you're all set.



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