[GRASSLIST:487] Re: measure lenght of vector

[H Bowman]

> > Do you want to measure few segments interactively on monitor or 
> > many segments noninteractively?
> 
> Sorry if my wording was vague.  By ``segment'' I meant the second, a 
> fraction of ONE line in a vector map, defined between two points.  And
> there is only need to measure a few of them, perhaps interactively.  I
> thought of `cropping' the vector map (a shoreline from GMT) by setting
> the region and <vector utility similar to r.resample>, but then how
> can I measure the length of that vector? 


mind the fractal problem, best to compare coastline length as compared
to other areas or as percentage of total length, but all at the same
sample resolution.

see
http://www.iemar.tuwien.ac.at/modul23/Fractals/pages/221rugged.html



A brute force way might be 
v.to.sites -a
s.out.ascii
crop as needed, and sum distances between each pair of points
  sqrt(dx*dx + dy*dy)



H.