[GRASS-user] Loss of data using v.net

[דור פרידמן]

I'm trying to build a network in GRASS in order to find the shortest path
from any settlement out of 1120 (points), to one waste treatment facility
out of 27 (points). I plan to use v.net.distance which is designated to
this purpose, and to define source and destination points using a column
called "type". In that column I have assigned the settlements layer with
the number 5 and the treatment facilities with 1.

My problem occurs when I try to create the network using v.net; If I define
nodes layer (nlayer=2) to be 2, I lose all the points and can't find it,
even by using v.extract. Otherwise (when nlayer=1) the attributes
describing type are being auromatically changed to 4, which is the type
attribute for roads.

Since I have 1120 I find that using from_cat instead of a SQL restriction
will be too hard.

Any one has an idea why I'm losing this crucial data and how can I prevent
it from happening?

Thanks in advanced,

Dor
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