[PROJ] Altitude question

[Even Rouault]

Le 01/12/2021 à 08:59, Roger Oberholtzer a écrit :
> How does one determine the expected type of altitude (geoid or
> ellipsoid) that a transformation expects? For example EPSG:5845
> (Sweref99 + RH2000).
A compound CRS such as the above one will necesarily have the vertical 
axis as a orthometric height (geoid). Never an ellipsoid one
>
> If I look at things like https://epsg.io/6499-cs or
> https://epsg.io/5208 (which are referenced in the RH2000 definition)
> the definition is not shown correctly in my browser. And I do not get
> information for them via projinfo. It says the CRS is not found. Which
> I guess is correct.
Transformation EPSG:5208 does exist in EPSG

https://epsg.org/transformation_5208/RH2000-height-to-EVRF2007-height-1.html

but it is not available in the PROJ database as the corresponding 
transformation method doesn't exist as a PROJ operation (could likely be 
implemented as IOGP publishes the formula, but this remains to do)

Even

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