A library providing vector geometry services

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3
votes
2answers
406 views

GDAL with GEOS support, pandas and VTK using python on Windows?

So far I have been using OSGeo4W shell (or OSGEO install) as really convenient way to use python together with additional packages, namely gdal, shapely, numpy, scipy and matplotlib. I was happy till ...
2
votes
1answer
9 views

What does the GEOS LineString “normalize()” routine really do?

What does the GEOS LineString "normalize()" routine really do? GEOS has virtual void geos::geom::LineString::normalize() with the documentation: A normalized linestring has the first point which ...
3
votes
0answers
31 views

Can I reorder the points in a GEOS LineString?

Using libgeos, when I buffer() a polygon and then getExteriorRing() [to make a slightly smaller outline copy of the polygon just inside the original], it seems that which point on the new geometry is ...
3
votes
0answers
8 views

Casting group of two polygons with rgeo returns nil

Here's an array of 2 polygons I'm trying to cast into a multipolygon (wkt string format). The polygons are in a linear CRS, SRID:3361 ["POLYGON ((990863.9961167622 709913.6373089257, ...
1
vote
0answers
18 views

geoPHP pointOnSurface always returns null

Using geoPHP with geos installed. pointOnSurface() for a valid polygon always returns null. While other functions such as centroid() work fine. Example: geoPHP::geosInstalled(); //true ...
1
vote
0answers
71 views

Error and kernel dies with shapely/geos inside Jupyter notebook

I have a Python 2.7 script (code below) that scrapes data from a table on the web and draws a map. It runs fine from the command line using $ python bears.py When I run the identical script from ...
1
vote
0answers
120 views

How to get full 16 bits range using RasterSymbolizer and ColorMap ramp?

I am attempting to get the full 16 bits values of my DEM (stored as TIFF files) rendered in WMS tiles (png format). For this I use GeoServer 2.5 and a RasterSymbolizer with a ColorMap of type "ramp". ...
1
vote
0answers
350 views

Why does polygon.intersection(complex_linestring) split the linestring and mess up Z?

I have a complex (self crossing) line with Z values which I'd like to truncate to the area inside a box. The problem is Shapely splits the line into simple (non-crossing) sections and the Z value at ...
1
vote
0answers
505 views

Get the distance between 2 WGS84 GEOSGeometries

I currently want to check if 2 given GEOSGeometry objects of type Point are within 100m of each other. (length flexible) Looking at previous asked questions on this topic, most of the answers were ...
1
vote
0answers
81 views

GEOS: how to access Noder functionality through the C API

All this stuff looks rather useful: http://geos.osgeo.org/doxygen/classgeos_1_1noding_1_1Noder.html However, from the GEOS README file: The C++ interface should not be used directly; the geos ...
0
votes
0answers
37 views

Understanding output point in polygon solution?

My question refers to an old solution which is provided in How do I find out if a given lat lon is in a KML Linear ring using shapely? Using python3 I needed to update the code somewhat to get this ...
0
votes
0answers
14 views

Trouble Changing Paths for geospatial libraries

I am currently using Python 2.7, Django 1.8 and Windows 7. I am trying to set the Windows environment variables, as per the instructions here . When I try to do this using the Powershell, I get the ...
0
votes
0answers
140 views

GEOS assertion failed

The following script fails, if I import the 'rasterstats' library. import rasterstats import ogr geom1 = ogr.CreateGeometryFromWkt('POLYGON ((415924.806155724043492 ...