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Re: Points within polygons
Posted by: Mike McCutcheon
Date: April 09, 2010 01:50AM

The only other problem I have with distance() is that it doesn't seem to handle calculations very well in high latitudes.

I used it to categorize 16,000 places into regions. I only have 24 places which distance() can't help me find a region for and they are all in high latitudes at various different longitudes.

I use distance() to identify a polygon whose distance to each point = 0, but it can't find a polygon which contains these 24 points. Some of the points are quite close to a boundary between two polygons, but some are hundreds of miles from the boundaries, right in the middle of their polygon.

It's not a huge problem to me as I can obviously manually categorize 24 places but it might indicate some mathematically problem to someone brighter than me.

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