[PROJ] Migrating to PROJ-9

[Nicolas Bellaiche]

Hi all, 

I'm migrating my C++ code from PROJ4 to PROJ9 and I meet a worrying issue with the computation. Some of my regress tests don't pass so I've tested with cs2cs and gets the same difference: 



PROJ4 

echo [ callto:652760.73700000 | 652760.73700000 ] [ callto:7033791.24300000 43 | 7033791.24300000 43 ] .64200000 | cs2cs +init=IGNF:LAMB93 +to +init=IGNF:RGF93: 

4070327.25 [ callto:166078.93 4891298.61 | 166078.93 4891298.61 ] 




PROJ7 or PROJ9 

echo [ callto:652760.73700000 | 652760.73700000 ] [ callto:7033791.24300000 43 | 7033791.24300000 43 ] .64200000 | cs2cs +init=IGNF:LAMB93 +to +init=IGNF:RGF93: 

4070355.05 [ callto:166080.07 4891332.24 | 166080.07 4891332.24 ] 






I suspect that PROJ7 and PROJ9 don't read properly the geoid file but I'm not sure. Someone can help me tracking and fixing this problem? 

Thanks, 

Nicolas Bellaiche 
Institut Géographique National France 
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