Hi Andrea,
I am sorry for my late answer.
You probably are right about EPSG:2154 though I am not a specialist...
In the near future, I'll not be working anymore with these data.
Instead of French departments I'll need world states.
And actually... I don't know "where" I can get these data for free... do
you?
I would need to put these world states in a PostGIS table as
multipolygons the same way I do with the French departments.
For now, to get used to GeoServer and Openlayers, I'll be working with
these data (French departments + points) because it is a working set...
I am just trying to solve one problem after the other...
But, yes indeed, you are totally right: "Knowing the exact spatial
reference system of your data is important, otherwise you don't really
know what part of the earth the data refers to."
So maybe, if it's not too much asking, could you advise me some good
literature about these issues?
Anyway: thank you for your time!
Best regards,
--
Lmhelp
On 05/07/2011 7:31 PM, Andrea Aime wrote:
On Sat, May 7, 2011 at 7:22 PM, Lmhelp<[email protected]> wrote:
> Thank you Andrea.
>
> Thank you for your explanations about asking PostGIS directly and so on.
> It's a very good start for me!
>
>> By the numbers you get it seems your data is in some projected coordinate
>> system. Which one, I cannot know.
>
> Ah ok... Can it be Lambert93 (SRID = 310024140)?
Uh, may be? But I never heard of that SRID, it's not in the official EPSG
database, nor seems a common ESRI one.
Do you mean EPSG:2154:
PROJCS["RGF93 / Lambert-93",
GEOGCS["RGF93",
DATUM["Reseau Geodesique Francais 1993",
SPHEROID["GRS 1980", 6378137.0, 298.257222101, AUTHORITY["EPSG","7019"]],
TOWGS84[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0],
AUTHORITY["EPSG","6171"]],
PRIMEM["Greenwich", 0.0, AUTHORITY["EPSG","8901"]],
UNIT["degree", 0.017453292519943295],
AXIS["Geodetic longitude", EAST],
AXIS["Geodetic latitude", NORTH],
AUTHORITY["EPSG","4171"]],
PROJECTION["Lambert Conic Conformal (2SP)", AUTHORITY["EPSG","9802"]],
PARAMETER["central_meridian", 3.0],
PARAMETER["latitude_of_origin", 46.5],
PARAMETER["standard_parallel_1", 49.0],
PARAMETER["false_easting", 700000.0],
PARAMETER["false_northing", 6600000.0],
PARAMETER["scale_factor", 1.0],
PARAMETER["standard_parallel_2", 44.0],
UNIT["m", 1.0],
AXIS["Easting", EAST],
AXIS["Northing", NORTH],
AUTHORITY["EPSG","2154"]]
Knowing the exact spatial reference system of your data is
important, otherwise you don't really know what part of the
earth the data refers to.
Normally the knowledge of the coordinate reference system
is associated in some metadata file, or just otherwise specified
by the data provider
Cheers
Andrea
-- ------------------------------------------------------- Ing. Andrea
Aime GeoSolutions S.A.S. Tech lead Via Poggio alle Viti 1187 55054
Massarosa (LU) Italy phone: +39 0584 962313 fax: +39 0584 962313
http://www.geo-solutions.it http://geo-solutions.blogspot.com/
http://www.youtube.com/user/GeoSolutionsIT
http://www.linkedin.com/in/andreaaime http://twitter.com/geowolf
------------------------------------------------------------------------------
WhatsUp Gold - Download Free Network Management Software
The most intuitive, comprehensive, and cost-effective network
management toolset available today. Delivers lowest initial
acquisition cost and overall TCO of any competing solution.
http://p.sf.net/sfu/whatsupgold-sd
_______________________________________________
Geoserver-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/geoserver-users
