[GRASS-windows] (no subject)

[Louis Becker]

Hi

I have downloaded a number of file sets, but the first two I used are
called 33J and 33K, where number 33 indicates the UTM Zone 33 and J is a
tile of that with bottom left corner 32S 12E and top right corner 24S
18E (8 x 6). 33K is the tile just north of 33J.

A file set from this site comes with the following folders and (files):

Clutter - (dt, dt.hdr, index and menu)
Dtm - (dtm, dtm.hdr, index and projection)
Map - Geotif files (.TAB, .tfw, .tif and index)
Ortho - (.TAB, .tfw, .tif and index)

I am only able to define a location from a Georeferenced file if I use
the DTM file under DTM (let's call it DtmLocation). If I then display
the region settings, I get the following for DTM 33J:

projection: 0 (x,y)
zone:       0
north:      7345125
south:      6453125
west:       192375
east:       807375
nsres:      250
ewres:      250
rows:       3568
cols:       2460
cells:      8777280

If I use the tif file from the Map folder to create a location (let's
call it UTMLocation), I get the following if I display the region
settings for 33J:

projection: 1 (UTM)
zone:       -33
datum:      wgs84
ellipsoid:  wgs84
north:      7345000
south:      6453000
west:       192500
east:       807500
nsres:      125
ewres:      125
rows:       7136
cols:       4920
cells:      35109120

If is not an issue to import the dtm file into the 33J_DtmLocation, but
is not properly referenced for further use. If I want to import the dtm
into the 33J_UTMLocation, I have to override the projection check.

Defining a location for 33K DTM yields:

projection: 0 (x,y)
zone:       0
north:      8231125
south:      7340125
west:       176375
east:       823375
nsres:      250
ewres:      250
rows:       3564
cols:       2588
cells:      9223632

Defining a location (called 33 of 33K_UtmLocation) Tif yields:

projection: 1 (UTM)
zone:       -33
datum:      wgs84
ellipsoid:  wgs84
north:      8231000
south:      7340000
west:       176500
east:       823500
nsres:      125
ewres:      125
rows:       7128
cols:       5176
cells:      36894528

I am able to import the 33K_Dtm into the 33K_UtmLocation by overriding
the projection check. If in now try to re-project using r.proj for the
raster file in 33J_UtmLocation into the 33K_UtmLocation, then it just
does not seem to work. I also check the flag "Do not perform region
cropping optimization", but is still only import only a small "slice" of
the adjacent tile.

I have tried importing the DTM using r.in.arc, but it cannot read the
projection files, etc.

How can I do this?

Louis


-----Original Message-----
From: Moritz Lennert [mailto:mlennert at club.worldonline.be] 
Sent: 01 October 2008 22:40
To: Louis Becker
Cc: grass-windows at lists.osgeo.org
Subject: Re: [GRASS-windows] (no subject)

On 01/10/08 16:48, Louis Becker wrote:
> Hi
> 
> I am trying to import the DTM files I found in the following location.
> 
> http://www.computamaps.com/en/catalog/index_2.html
> 
> The details given for the files are stipulated as follows.
> 
> Format: Planet 2.8 (r), ArcInfo Grid
> Projection: UTM
> Ellipsoid: WGS84
> Resolution: DTM and Clutter 250m, Orthoimage and Map 125m
> 
> I am able to import the DTM files if I override the projection check, 
> but then of course patching files together becomes a bit difficult. Is

> there maybe an easy way out of this?

What is the projection of the location you import the files into ?

Moritz