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Hi,
thanks Leyan.
Unfortunately that knowledge doesn't help to solve rhe problem.
I looked proj tables and I noticed that there is four different
codes with same parsed items.
And further, why QGIS makes its own variant of the name which is
not used anywhere in Finland. I know there is no standard for
those names but...
I'm continuing to find some solution for this "niche".
Cheers,
Kari
On 12/18/2014 10:23 PM, Leyan wrote:
On 12/18/2014 06:35 PM, Kari
Salovaara wrote:
Hi,
in Finland we have map datasets free of charge to download from
The National Land Survey of Finland (NLS). See http://www.maanmittauslaitos.fi/en/opendata
From Topographic Database You can download in ESRI shape format
any Finnish map area. In each area You'll get a number of
shapefiles related to category and each category has also a
*.prj file.
The problem arises when You make a layer from any of these
shapefiles in following example;
1. set project CRS to Finnish ESPG:3067 ( which is on the list
EPSG:3067 - ETRS89 / ETRS-TM35FIN)
2. make a layer from shapefile, as it has *.prj which starts
like
PROJCS["ETRF89_ETRS_TM35FIN",GEOGCS["GCS_ETRS89",DATUM["D_ETRS_1989"....
You expect the layer CRS to be 3067 but when You look to layer
properties it shows 3047 (in the dialog list EPSG:3047 - ETRS89
/ ETRS-TM35)
(which means, I think,
PROJCS["ETRF89_ETRS_TM35",GEOGCS["GCS_ETRS89",DATUM["D_ETRS_1989")...
small but nasty difference.
This problem can cause difficulties when creating scripts for
automation etc.
And very odd is that when You have created an empty project with
CRS set to 3067 and create a shapefile its *.prj file starts
PROJCS["ETRS89_TM35FIN_E_N",GEOGCS["GCS_ETRS_1989",DATUM["D_ETRS_1989",
but in this case the EPSG is 3067.
For my knowledge ETRS-TM35FIN is always and only EPSG:3067.
Could someone explain is this failure in QGIS or GDAL/OGR or
PROJ.4?
This problem has been tested in 2.6.1 (latest update in
OpenSuse12.3) and 2.7.0 (nightly) versions and both linux and
win 7 environments.
Finnish QGIS society are waiting this Christmas Question answer
with interest. ;)
With warm and kind regards,
Kari
PS. This has been discussed here locally without any final
understanding. Some guess has been that program only looks and
takes first some nearly suitable code and uses it.
It seems the proj4 string for both CRS is the same in my local
installation. Is it the same for you ? In that case, they are
exactly equivalent for QGis. When QGis finds a dataset without a
clear CRS code, it will parse the proj4 string to find the
coordinate system and stop at the first corresponding one.
Regards,
Leyan
--
Kari Salovaara
Hanko, Finland
"Volunteers do not necessarily have the time; they just have the heart."
~ Elizabeth Andrew
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