[PROJ] some questions about the Barn Raising

[Even Rouault]

On mardi 16 avril 2019 19:41:52 CEST Even Rouault wrote:
> Eduardo,
> 
> > I want to promote the initiative "/GDAL Coordinate System Barn Raising"/
> > because in Costa Rica there has recently been a change of CRS - from
> > CRTM05
> > (EPSG 5367) to CR-SIRGAS (EPSG 8906)
> 
> You meant CR-SIRGAS (EPSG *8908*) right ?
> 
> This was a very interesting use case that exhibit a few bugs in PROJ I've
> just fixed per https://github.com/OSGeo/proj.4/pull/1427 (for PROJ 6.1)

I didn't detail the oddity. But the EPSG:8913 transformation (CR05 to CR-
SIRGAS (1)) uses Geographic 3D CRS as source and target CRS for the 
transformation, wheras the transformation method is EPSG:9606 method (Position 
Vector transformation (geog2D domain)). I got confirmation from IOGP that this 
entry is bogus, and will be replaced by a new one in the next release of the 
EPSG dataset to use the corresponding Geographic 2D CRS. And that was 
apparently the only such erroneous case in the database, so definitely a very 
interesting use case :-)

Even

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