Monthly Archives: March 2010

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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Toronto’s Human Centre, part 2: by neighbourhood

Beware throwaway comments; that way overanalysis lies. This was a challenge. Taking the 2006 neighbourhoods population into account, the human centre of Toronto is at 43.717955°N, 79.389828°W … … pretty close to the one I’ve already worked out by ward. … Continue reading

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finding the nearest thing to another thing

Something I used to have to do a lot was to maintain a table of the nearest houses to prospective wind farm layouts. While the list of houses didn’t change very much, the layouts did. I came up with an … Continue reading

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toronto’s human centre

Since it was trivial to calculate the centre of the city, I thought I’d do something a little more complex: calculate the centre of the city, weighted for population. I scraped the 2006 population data by ward from the City … Continue reading

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Japanese Map Symbol for a windmill

I’m rather taken with the symbol that Japanese maps use for wind mills and wind turbines. I’ll try to modify it for use in QGis. Update: so how does this look? I cleaned up the blade angles, added line end-caps, … Continue reading

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a minor revelation about road segments

I’m still learning how Toronto encodes its roads – and whether this is a common practice. Between intersections, roads are stored as polyline segments. Kennedy Road (blue) and Eglinton Ave E (red) are shown below as a series of road … Continue reading

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Toronto’s Angles

As many Canadians will tell you, most Torontonians are a bit skewed. While others might have different explanations, I put it down to our road grid. What we call north in the city is actually some 16.7° west of north. … Continue reading

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but where am i, really?

In my first post I asked where am i? The gps in my phone said I was standing at 43.73066°N, 79.26482°W. In real life, I was standing at the junction of Kenmark Blvd and Chevron Cres. With the Open Toronto … Continue reading

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Finding the exact geographic centre of Toronto

Spacing has alluded to it. The Ontario Science Centre makes bold (and incorrect) claims about it. But here’s the real deal. If you consider Toronto to be defined by its city wards, the centre of Toronto lies at 43.725518°N, 79.390531°W. … Continue reading

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oooOOOooh!

Now that’s a bit better. And I did it with only mild shapefile abuse. You can load the DBF component of a shapefile into Openoffice Calc. Columns get given headers which describe their format. By pasting in the candidates column, … Continue reading

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