[Routing] Derive data: number of lanes and capacity

[Paul Johnson]

On Thu, 22 Jul 2010 13:18:15 +0200, Marcus Wolschon wrote:

> Tom Müller wrote:
>>> There is an explicit tag
>>> lanes=<number>
>>> http://wiki.openstreetmap.org/wiki/Key:lanes
> 
>> yes. I know. But it's set pretty rarely. For Berlin it's set for
>> approx. 6% of all highways ... So I was just wondering if there are any
>> defaults which are deriveable by the highway-type or so?!
> 
> I would assume that all highway=* to be lanes=1 (residential, secondary,
> service,...) except motorways with lanes=2
> 
> Maybe highway=primary be 2 lanes too.

There's a lot of one-lane-each-way primaries in the US.  And thanks to 
some continent-wide data torquing by NE2, a lot of one-lane-each-way 
trunks.  The former's a fact of life, America has a lot of extremely 
rural primaries running through badlands, mountain peaks or otherwise 
just don't require extra capacity despite connecting cities.  The latter 
probably needs to be solved with a ban.