[Openstreetmap-dev] Node / line segment database statistics separation

[Lars Aronsson]

Tom Carden wrote:

> In a 2x2 grid street pattern, there are 4 nodes and 4 lines, 
> right?  But in a 3x3 there are 9 and 12, and in a 4x4 there are 
> 16 and 24, and so on.  For n x n, there are n^2 nodes and (2n^2 
> - 2n) lines.

A very common pattern is that each road segment between street 
corners (or countryside crossroads) has a slight bend, which 
requires one or more intermediate nodes.  Considering the long 
runs of country roads and motorways, I think the vast majority of 
nodes are such that only connect line segments into long roads.  
Thus the number of nodes should be very close to the number of 
line segments.


-- 
  Lars Aronsson (lars at aronsson.se)
  Aronsson Datateknik - http://aronsson.se