[PROJ] PROJ 9.3.0 EPSG behavior on debian:sid versus osgeo/proj image

[Even Rouault]

David,
> 1. EPSG code returned from `proj_identify` on one platform and not the 
> other even with the same PROJ source. Assuming I didn't make a dumb 
> mistake this would suggest some dependency is changing the behavior of 
> how the proj.db database is read/used...right? The only thing I can 
> think of is libtiff or sqlite3.

Likely that your pyproj install bundes PROJ 9.2.1 and not 9.3.0 since:

$ docker run --rm -it osgeo/proj:latest proj --version
Rel. 9.3.0, September 1st, 2023

$ docker run --rm -it osgeo/proj:latest projinfo --identify "+proj=laea 
+lat_0=90 +lon_0=0 +x_0=0 +y_0=0 +R=6371228 +units=m +no_defs +type=crs"
[...]
Identification match count: 1
EPSG:3408: 70 %

> 2. The EPSG code created from a confidence of 70% is not considered 
> equivalent even though the API docs say "70% means that CRS are 
> equivalent, but the names are not equivalent."

Fixed per https://github.com/OSGeo/PROJ/pull/3879 (although this fix 
makes me slightly nervous)

As said many times, using PROJ.4 strings is bound to cause various 
issues. In particular, you will not be able to perform correct datum 
transformations.

Even

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