Tag Archives: ogr

geocoder.ca’s excellent database

geocoder.ca provides a crowdsourced postal code geocoder under the ODbL. You can download the database as CSV directly. Here’s a bash script to convert that text file into a (very large) point shapefile: Though the script is a bit Unix-centric, … Continue reading

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Not really getting the Azimuthal Equidistant projection right

All I really wanted to do is make a map like this: This is an Azimuthal Equidistant projection, with me at the centre (of course) and the rest of the world spread out in a fan by distance and bearing. … Continue reading

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current tools of my trade

Mark asked: What kind of GIS software are you using? Well, since you asked:- SpatiaLite: spatial awesome built on SQLite. I love it because I don’t need to play DBA. QGIS: for maps ogr: for file format futzing proj: for … Continue reading

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using CSV as a virtual data source

While we already know how to make trivial shapefiles with shapelib, sometimes that’s too tedious. Very frequently I get data in Comma Separated Value (CSV) format, and reliably importing/converting it can be a pain. Here’s our sample CSV file, library_test.csv: … Continue reading

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tale of two cities: coordinate reference systems, and what on earth is the maywood tot lot?

For reasons that are not particularly clear, the Toronto.ca|Open data is in two different coordinate reference systems (CRS), MTM 3 Degree Zone 10, NAD27 (EPSG 2019) and UTM 6 Degree Zone 17N NAD27 (EPSG 26717). This confuses QGIS even if … Continue reading

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