[GRASSLIST:886] Re: v.segment

[Hamish]

> > not sure if this would do what you want, but I made a module called 
> > d.bearing for the creation of transects, with some notes on dividing
> > up the main line segment into points along that line:
> > 
> > http://casoilresource.lawr.ucdavis.edu/drupal/node/149
..
> Thanks for the link. I may use it in the future. I modified my script
> to use. v.categories to add the category information (it was cleaner
> than using v.build). Making the stops with v.segment is fast. The slow
> part was building the attribute table at the end. It is still a bit
> slow (1 - 2 minutes for every 1000 points on my fairly new AMD box)
> but works. v.segment was great because the BBS (Breeding Bird Survey)
> routes are not straight, but follow road lines. They digitized the
> routes, but didn't have the stop information (observation locations),
> so I needed to break them up and number them so I can relate the bird
> information to the right piece of landscape. My solution wasn't
> perfect, but the day it took to figure it out was a lot quicker than
> going out with GPS unit to 173 routes scatted across Alberta. My
> v.makestops script needs some cleanup, but I will post it to the wiki
> later. I think it is potentially useful for others.


Dylan, Trevor,

you may want to check out Radim's v.lrs.* modules new in CVS.
  http://mpa.itc.it/radim/lrs/index.html

As for speeding up table filling, I think it is faster to write all
SQL statements to a file, then use just a single "db.execute input="
call. If this does speed it up significantly, let us know & we can add
the hint to db.execute help page.  (insert "time" on the command line
before the command to benchmark)


Michael:
> You could simply import them into a spreadsheet and export them as
> dbf. Then use v.db.connect. Even better if there was a txt2dbf
> utility. Maybe someone knows of one.

"db.in.ascii"
All the code to write it is already in v.in.ascii, see these threads:
  http://thread.gmane.org/gmane.comp.gis.grass.user/6038
  http://thread.gmane.org/gmane.comp.gis.grass.devel/5155

(I thought this was in the bug tracker already as a wish, guess not)

see also v.in.db.


Hamish