[GRASS-user] v.delaunay and v.category problem

[Maris Nartiss]

Please double check Your actions. Just tested here on 6.4-svn version:

v.delaunay -l input=D10k output=delone
v.db.addtable map=delone layer=1 {columns=cat integer}
v.category input=delone output=delone_cat option=add
type=point,line,boundary,centroid,area layer=1 cat=1 step=1
v.what -a map=delone_cat
east_north=624612.5216318436,6400722.6681744065
distance=214.46548410981273

No database record
East: 624612.52163184
North: 6400722.66817441
Map: delone_cat
Mapset: rm_this2
Type: Line
Id: 859
Garums: 639.105487
Layer: 1
Category: 859
Driver: dbf
Database: /home/maris/grass_data/Vidzeme_Balt93/rm_this2/dbf/
Table: delone_cat
Key column: cat

Maris.


2011/3/31, Andrea Pogliaghi <andrea.pogliaghi at gmail.com>:
> just to make it clearer.... if I do the above steps with v.delaunay, then I
> create the table with v.db.addtable and then I run v.category, it works
> fine.
> If I do the same steps with v.delaunay with the -l flag (and I have to,
> since I need the lines), then it doesn't.
>
> cheers
> Andrea
>
>
> On Thu, Mar 31, 2011 at 4:37 PM, Andrea Pogliaghi <
> andrea.pogliaghi at gmail.com> wrote:
>
>> On Thu, Mar 31, 2011 at 2:54 PM, Maris Nartiss <maris.gis at gmail.com>wrote:
>>
>>> Hello,
>>>
>>> You have to connect Your vector map to database at first. Go to
>>> Databases->Manage database->New table (v.db.addtable) and run
>>> v.category afterwards.
>>>
>>>
>> That is exactly what I did.  In fact in my first message I wrote
>>
>>
>> "My idea was to run v.db.addtable to create a new empty attribute table,
>> then v.category to assign cat numbers and the v.to.db to compute and add
>> to
>> the attribute table the parameter I need (ie the length).
>> The problem is that when I run v.category nothing happens, and the
>> attribute table remains empty."
>>
>> cheers
>> andrea
>>
>>
>>> Maris.
>>>
>>>
>>> 2011/3/31, Andrea Pogliaghi <andrea.pogliaghi at gmail.com>:
>>> > Hi Maris,
>>> >
>>> > On Thu, Mar 31, 2011 at 10:25 AM, Maris Nartiss <maris.gis at gmail.com>
>>> wrote:
>>> >
>>> >> Hello,
>>> >> as attributes belong to triangle froming nodes, how should output look
>>> >> like? Every triangle should get all three atributes? And what about
>>> >> lines? Two attributes, as every triangulation line has two nodes at
>>> >> their end?
>>> >>
>>> >> It makes sense that no attribute is associated to v.delaunay lines
>>> output
>>> > because the features (lines in my case as I'm using the -l switch) are
>>> > different from the nodes (even if having an output attribute table
>>> > containing, for instance, the attributes of the two nodes of each line
>>> would
>>> > be useful), but that is not the point.
>>> > The issue I'm facing is that I want to create a new attribute table for
>>> > these delaunay_lines with a new unique cat value for every line and
>>> compute
>>> > the length of each line, as I need to know which is their min, max and
>>> avg.
>>> >
>>> > Cheers,
>>> > Andrea
>>> >
>>> >
>>> >
>>> >>
>>> >> Maris.
>>> >>
>>> >> 2011/3/30, Andrea Pogliaghi <andrea.pogliaghi at gmail.com>:
>>> >> > Hi all,
>>> >> > ...
>>> >> > Basically I run v.delaunay with the -l option to get lines instead
>>> >> > of
>>> >> > the
>>> >> > polygons, I get the resulting vector, but there is no attribute
>>> tables
>>> >> > associated to it.
>>> >> > ...
>>> >> > Ing. Andrea Pogliaghi
>>> >> > Milano - Italy
>>> >> >
>>> >>
>>> >
>>>
>>
>>
>