Datum not recognised

classic Classic list List threaded Threaded
4 messages Options
Reply | Threaded
Open this post in threaded view
|

Datum not recognised

Anders Kagervall
Hi,
I am quite new to GRASS and this is my first post to this list. To familiarize myself
with the software I have started to import data and now and then I get this warning:
"Datum <Rikets_koordinatsystem_1990> not recognised by GRASS and no parameters found"
Is this something I should be concerned about and how can I get rid of it?
My location is set up by choosing epsg number 3021 and the output from g.region -p is:

projection: 99 (Transverse Mercator)
zone:       0
datum:      ** unknown (default: WGS84) **
ellipsoid:  bessel
north:      7679625
south:      6124975
west:       1196975
east:       1900025
nsres:      50
ewres:      50
rows:       31093
cols:       14061
cells:      437198673


Best regards
Anders
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

Re: Datum not recognised

Markus Neteler
On Mon, Feb 8, 2010 at 4:51 PM, Anders Kagervall
<[hidden email]> wrote:

> Hi,
> I am quite new to GRASS and this is my first post to this list. To familiarize myself
> with the software I have started to import data and now and then I get this warning:
> "Datum <Rikets_koordinatsystem_1990> not recognised by GRASS and no parameters found"
> Is this something I should be concerned about and how can I get rid of it?
> My location is set up by choosing epsg number 3021 and the output from g.region -p is:
>
> projection: 99 (Transverse Mercator)
> zone:       0
> datum:      ** unknown (default: WGS84) **
> ellipsoid:  bessel
> north:      7679625
> south:      6124975
> west:       1196975
> east:       1900025
> nsres:      50
> ewres:      50
> rows:       31093
> cols:       14061
> cells:      437198673

The datum I have found here:
http://crs.bkg.bund.de/crseu/crs/eu-description.php?crs_id=dFNFX1JUOTAgLyBTRV9UTQ==

so the needed software change in GRASS might be:

svn diff lib/gis/
Index: lib/gis/datumtransform.table
===================================================================
--- lib/gis/datumtransform.table        (revision 40764)
+++ lib/gis/datumtransform.table        (working copy)
@@ -91,3 +91,4 @@
 tokyo   "towgs84=-147,506,687" "South Korea" " "
 # Campo Inchauspe, personal communication CONAE
(http://www.conae.gov.ar), Argentina:
 cai     "towgs84=-149.1,138.1,90.9,-0.142,0.344,0.301,0.388"
"Argentina" "provided by CONAE, Argentina"
+rt90   "towgs84=414.1,41.3,603.1,-0.855,2.141,-7.023,0.00" "Sweden
SE_RT90 to ETRS89" "http://www.crs-geo.eu"


but I don't manage to link it to EPSG 3021 in the location wizard.
We'll find out.

Markus
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

Re: Datum not recognised

Paul Kelly
In reply to this post by Anders Kagervall
On Mon, 8 Feb 2010, Anders Kagervall wrote:

> Hi,
> I am quite new to GRASS and this is my first post to this list. To familiarize myself
> with the software I have started to import data and now and then I get this warning:
> "Datum <Rikets_koordinatsystem_1990> not recognised by GRASS and no parameters found"
> Is this something I should be concerned about and how can I get rid of it?

Thanks for reporting this. The problem is simply that support for the
Swedish datum rt90 was never added to GRASS. I've now added it in SVN to
7.0, 6.5 and 6.4. Having the datum undefined will only cause problems if
you wish to reproject maps or data from/to your location.

If you've updated from SVN and want to include the datum parameters in
your location you can run
g.proj -c epsg=3021
and it will update the support files (PROJ_INFO in particular).

Paul
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user
Reply | Threaded
Open this post in threaded view
|

RE: Datum not recognised

Anders Kagervall
Wow, open source is fantastic! Less than one hour after my question I have two answers
and a fix submitted to the source repository. That's hard to beat for any support organization :-)

Anders

-----Original Message-----
From: Paul Kelly [mailto:[hidden email]]
Sent: den 8 februari 2010 18:06
To: Anders Kagervall
Cc: [hidden email]
Subject: Re: [GRASS-user] Datum not recognised

On Mon, 8 Feb 2010, Anders Kagervall wrote:

> Hi,
> I am quite new to GRASS and this is my first post to this list. To familiarize myself
> with the software I have started to import data and now and then I get this warning:
> "Datum <Rikets_koordinatsystem_1990> not recognised by GRASS and no parameters found"
> Is this something I should be concerned about and how can I get rid of it?

Thanks for reporting this. The problem is simply that support for the
Swedish datum rt90 was never added to GRASS. I've now added it in SVN to
7.0, 6.5 and 6.4. Having the datum undefined will only cause problems if
you wish to reproject maps or data from/to your location.

If you've updated from SVN and want to include the datum parameters in
your location you can run
g.proj -c epsg=3021
and it will update the support files (PROJ_INFO in particular).

Paul
_______________________________________________
grass-user mailing list
[hidden email]
http://lists.osgeo.org/mailman/listinfo/grass-user