Hello Steve
Le 19/02/2018 à 11:36, HRUDA Steve a écrit :
> I use the following Geodetic dataset in case of:
>
>
>
> * Apache SIS 0.7
> o EPSG dataset version 8.9 on “Apache Derby” version 10.11.
> * Apache SIS 0.8
> o EPSG geodetic dataset version 9.1 on “Apache Derby” version 10.11.
>
>
>
> Apache SIS 0.7 is able to do transformations from EPSG:4326 to
> EPSG:2062 by using an accuracy of 3000m
>
The accuracy of 3 km means that SIS 0.7 did not found or did not used
coordinate operation path explicitly defined in the EPSG database (3 km
is the default accuracy reported by SIS in those situations). At least
in latest EPSG database, there is an explicit transformation path
between those CRS with an accuracy of 10 metres:
http://epsg-registry.org/?display=entity&urn=urn:ogc:def:coordinateOperation:EPSG::8241
Reasons why SIS 0.7 did not used it while SIS 0.8 tries to use it could be:
* Maybe EPSG::8241 was not defined in EPSG 8.9 - I did not verified.
* Maybe EPSG::8241 was defined before, but evolution of SIS causes SIS
0.8 to follow this specification while SIS 0.7 ignored it.
We can verify by execution the following code with SIS 0.7:
CoordinateOperationAuthorityFactory opFactory =
((CoordinateOperationAuthorityFactory) CRS.getAuthorityFactory("EPSG"));
System.out.println(opFactory.createCoordinateOperation("EPSG::8241"));
If you get something like "No such coordinate operation", this means
that EPSG::8241 was not defined in EPSG 8.9. If you get something like
"No method found for Matrid to ED50 polynomial", this means that
EPSG::8241 was defined in EPSG 8.9 but SIS 0.7 ignored it. The only
thing sure is that "Matrid to ED50 polynomial" has never been
implemented yet in SIS.
Regards,
Martin
