1
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1answer
22 views

Extracting z values from shapefile using OGR Api

Is there an example of how we can extract the z value from a shp file given the x,y coordinate value (namely utm) using gdal/ogr c++ lib? alternatively, would it be easier if we convert the shp file ...
2
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0answers
85 views

Custom python datasource to QGIS

I'm working on a homebrew spatial feature data format, and using Python to write it's API. It occoured to me that use some tool like QGIS to display my data would be very nice to have, for debug/test ...
7
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2answers
2k views

Generating GeoJSON with Python

Hi I want to programatically create a GeoJSON file using polygons from a shapefile but adding attributes from my own application. This is easily done for a shapefile: def ...
4
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1answer
824 views

How to programatically populate a shapefile field with polygon areas in OGR?

I'm trying to programatically populate a shp field with polygon areas: import sys import ogr ds = ogr.Open( 'tttttttttt.shp', update = 1 ) if ds is None: print "Open failed./n" sys.exit( 1 ...
5
votes
1answer
350 views

Combined area of all features within features of another layer

I have a grid shapefile (basically, a half-degree grid of the world, where each cell has a unique id number), and a set of files with features. I want to record for each grid cell, all the areas ...