[GRASSLIST:5665] Re: Creating DTM from shapefiles

[Māris Nartišs]

Unfortunatly that v.append failed to work. Do realy such easy and
common thing like joining 2 vect data layers is impossible in such
great GIS app?
Maybee I did somtn wrong, so heres error msg. (both vector files are
points - augstump = height points from shapefile and izol_p = isolines
converted to points with v.to.points):

v.append vect1=augstump vect2=izol_p vmerged=test_izolp_augstp
vtype=point vlayer=1
Exporting 74 points/lines...


74 features written
Exporting 172622 points/lines...


172622 features written

GRASS_INFO_WARNING(4919,1): Datum 'unknown' not recognised by GRASS
and no parameters found. Datum transformation will not be possible
using this projection information.
Over-riding projection check.
Proceeding with import...
Layer: test_izolp_augstp
DBMI-DBF driver error:
Column 'CAT' already exists (duplicate name)
Cannot create table.
Error in db_execute_immediate()


Cannot create table: create table test_izolp_augstp (cat integer, CAT
integer, HEIGHT double precision, AUGST double precision)





On Sun, 06 Feb 2005 17:55:30 -0700, Michael Barton
<michael.barton at asu.edu> wrote:
> Maciek,
> 
> Not to worry. GRASS is a BIG program and hard to know what everything
> does--especially across 2 versions. However, I've run into the same problem
> recently and so have been testing various options of patching.
> 
> I *think* the script lets you patch points, lines, or areas (there is a
> selection pull-down to choose). I also *think* it preserves the attribute
> files. I don't know how it combines them however, especially if they have
> different fields. It uses ogr2ogr, so the documentation to that may help--or
> just a bit of trial and error.
> 
> I wrote it on a plane to a meeting in Washington, DC and so haven't had time
> to test it much. I also need to add a brief routine at the end to clean up
> the temporary files it makes and ask someone to test it for temp file
> security (assuming I write the routine to delete the temporary files). But
> it does show the advantages of using even simple shell scripting in GRASS.
> The ease of making a nice GUI interface in scripts is thanks to Radim and
> Markus.
> 
> Michael
> ____________________
> C. Michael Barton, Professor of Anthropology
> School of Human Evolution and Social Change
> PO Box 872402
> Arizona State University
> Tempe, AZ  85287-2402
> USA
> 
> Phone: 480-965-6262
> Fax: 480-965-7671
> www: <www.public.asu.edu/~cmbarton>
> 
> > From: Maciek Sieczka <werchowyna at pf.pl>
> > Date: Mon, 07 Feb 2005 00:32:33 +0100
> > To: Michael Barton <michael.barton at asu.edu>, Maris Nartiss
> > <maris.nartiss at gmail.com>, <grasslist at baylor.edu>
> > Subject: Re: [GRASSLIST:5654] Re: Creating DTM from shapefiles
> >
> > Guys
> >
> > Michael is right. I'm sorry for my messing. Indeed only the cats are
> > preserved in 5.4 v.patch. And indeed v.patch works the same in 5.7/6.0. When
> > I wrote that labels are preserved by v.patch in 5.4 I was wrong. Patching
> > cats is all I could do and why I came to conclussion that I managed to patch
> > labels  once - I don't know. Obviously it mixed somehow in my mind and I
> > wanted to be  the wise ass. That was dumb not to doublecheck what I was
> > writing about before posting to the list. I hope I won't be taken as dumb in
> > general, though :).
> >
> > Thanks for the sript Michael. Haven't tried it yet. Does it let me to patch
> > points and lines?
> >
> > Maciek
> >
> > P.S.
> > Anyway, there could be some note in the v.patch manual regarding it's
> > current limitations and eventual alternatives. Whom should I bother with
> > this?
> >
> > ----- Original Message -----
> > From: "Michael Barton" <michael.barton at asu.edu>
> > To: "Maciek Sieczka" <werchowyna at pf.pl>; "Maris Nartiss"
> > <maris.nartiss at gmail.com>; <GRASSLIST at baylor.edu>
> > Sent: Sunday, February 06, 2005 7:09 AM
> > Subject: [GRASSLIST:5654] Re: Creating DTM from shapefiles
> >
> >
> >> Maciek and Maris,
> >>
> >> V.patch DOES work in GRASS 5.7/6.0. However, it works like it did in GRASS
> >> 5.4. That is it simply combines vectors and their cat file. It does not
> >> combine any attribute tables they may have.
> >>
> >> I've written a simple script, using ogr2ogr, v.in.ogr, and v.out.ogr that
> >> seems to do this. However, I haven't had much chance to test it yet. If
> >> you'd like to give it a try, I attach it here.
> >>
> >> Michael
> >> ____________________
> >> C. Michael Barton, Professor of Anthropology
> >> School of Human Evolution and Social Change
> >> PO Box 872402
> >> Arizona State University
> >> Tempe, AZ  85287-2402
> >> USA
> >>
> >> Phone: 480-965-6262
> >> Fax: 480-965-7671
> >> www: <www.public.asu.edu/~cmbarton>
> >>
> >>
> >>> From: Maciek Sieczka <werchowyna at pf.pl>
> >>> Date: Thu, 3 Feb 2005 19:07:16 +0100
> >>> To: Maris Nartiss <maris.nartiss at gmail.com>, <GRASSLIST at baylor.edu>
> >>> Subject: [GRASSLIST:5626] Re: Creating DTM from shapefiles
> >>>
> >>> From: "Maris Nartiss" <maris.nartiss at gmail.com>
> >>>> Hi,
> >>>>
> >>>> I'm beginner with Grass and I have beginners problems :)
> >>>>
> >>>> I have 2 shape files one with lines and second with points. Both of
> >>>> them have HEIGHT parameter in attribute tables (lines - int, points -
> >>>> float (double precision)). To do some modeling, I need to create
> >>>> surface from those files.
> >>>> I read some docs and understood, that best surface creation algorithm
> >>>> in Grass it RST.
> >>>> Now I have Q - how to combine both source vector data layers to feed
> >>>> them to v.surf.rst?
> >>>> I was trying 2 solutions, but, due to lack of knowledge, both of them
> >>>> where dead ends.
> >>>> 1) Using v.patch to combine both vector data sources
> >>>
> >>> v.patch in 5.7/6.0 is not operational yet. You'll find some workarounds
> >>> in
> >>> recent archives of grass5 list. You can also try patching two such vector
> >>> layers (points and lines) with v.patch in Grass 5.4/5.5. It should
> >>> preserve
> >>> labels of both input layers properly. But always check whether the labels
> >>> were really preserved as they should. It happened to me with one
> >>> particular
> >>> dataset that they were not for some reason (though maybe it was the
> >>> dataset
> >>> fault). If all is ok then import into 6.0 with v.convert.
> >>>
> >>>> 2) Convert lines to points and then combine them with v.patch
> >>>> both worked fine but when I used d.what.vect I got only "Database
> >>>> connection not defined".
> >>>
> >>> v.patch doesn't output any database - so there is nothing to be
> >>> connected.
> >>> Moreover the vector layer resulting from v.patch in 5.7/6.0 has all the
> >>> cats
> >>> of the input layers preserved, so you result in having lots of features
> >>> with
> >>> the same cat, thus it is not virtually possible to prepare an appropriate
> >>> database manually. All you get in an output of that v.patch is a
> >>> vectorial
> >>> drawing actually.
> >>>
> >>>> Any ideas, links to howtos etc. welcome.
> >>>>
> >>>> Maybe as a newbie with some ArcView background I'm unable to
> >>>> understand some Grass specific things, who cause my problems, but
> >>>> currently Grass docs aren't very helpful, mainly cuz they a bit
> >>>> outdated :(
> >>>
> >>> v.patch manual should contain some remarks on these issues until it's
> >>> fixed
> >>> IMHO.
> >>>
> >>>> TNX for reading this,
> >>>> Maris.
> >>>
> >>> Cheers
> >>> Maciek
> >
> 
>