[GRASSLIST:858] Re: v.segment
dylan.beaudette at gmail.com
Tue Apr 25 11:32:13 EDT 2006
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:
On Apr 24, 2006, at 11:26 PM, Trevor Wiens wrote:
> On Mon, 24 Apr 2006 23:00:15 -0700
> Michael Barton <michael.barton at asu.edu> wrote:
>> Use v.category to attach categories.
>> V.to.db to add information to attribute table? I don't know if this
>> with v.segment output or not. In fact, I can't figure out how
>> works either.
>> Create a dbf file using a spreadsheet (OO or Excel -- OO works
>> better). Call
>> the first column "cat", make it an integer, and fill it with a
>> sequence of
>> numbers equal to the number of points you have. Then use v.db.connect
>> link them up.
> Thanks, but not really what I wanted to hear.
> I wrote a script to make stops on Breeding Bird Survey route lines at
> equal intervals, and manipulated the category values to be meaningful.
> Unfortunately, v.segment doesn't create an attribute table so I used
> v.build with the cdump option to get a list of the categories and then
> used db.execute to add them one by one into a table. Very slow.
> I can see now I could get a list easier using v.category, but
> unfortunately it won't automagically create an attribute table with the
> categories in it.
> I was hoping for an easy way to do this as it would make the script a
> lot more elegant and faster, but it appears that my ugly hack is the
> only solution.
> Trevor Wiens
> twiens at interbaun.com
> The significant problems that we face cannot be solved at the same
> level of thinking we were at when we created them.
> (Albert Einstein)
Soils and Biogeochemistry Graduate Group
University of California at Davis
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