[OSM-talk] Re: One way streets

[Simon Hewison]

Richard Fairhurst wrote:
> I'm tempted to agree with Oliver. The danger of having 'one way' 
> dependent on the direction of the segment is that, if a segment is 
> accidentally reversed, the data becomes wrong. Having 'oneway=NE', or 
> whatever, is independent of this.

I've already written this "backwards segment" reporting utility, and if 
I run it regularly, then it would be reasonably easy to identify 
segments that have become accidentally flipped around the wrong way.

Oh, I have written this reporting utility, and it's already found quite 
a few. I'll wikify the results from the latest planet.osm in a readable 
form tomorrow for people to see what the findings are. Then people can 
make an informed decision as to whether or not it's a good idea.

At the moment, it runs against planet.osm, which means it's monthly, but 
it's easy enough at present to look at all ways in the database (minus 
the TIGER import) and check them (because there's not an enormous 
numbers of ways), so it could run more often, providing I don't hammer 
the api too badly.

--
Simon Hewison