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Consistency of crs.is_geographic between different EPSG representations

See original GitHub issue

When creating an EPSG:4326 projection using a proj4 string, the value of the proj.crs.is_geographic property depends on whether definition_string() or crs.to_proj4(4) was used for initialization.

In [1]: import pyproj                                                                                                                                                                                                                        

In [2]: pyproj.Proj('EPSG:4326').crs.is_geographic                                                                                                                                                                                           
Out[2]: True

In [4]: pyproj.Proj('EPSG:4326').crs.to_proj4(4)                                                                                                                                                                                             
Out[4]: '+proj=longlat +datum=WGS84 +no_defs +type=crs'

In [5]: pyproj.Proj('EPSG:4326').definition_string()                                                                                                                                                                                         
Out[5]: 'proj=longlat datum=WGS84 no_defs ellps=WGS84 towgs84=0,0,0'

In [6]: pyproj.Proj(pyproj.Proj('EPSG:4326').crs.to_proj4(4)).crs.is_geographic                                                                                                                                                              
Out[6]: True

In [7]: pyproj.Proj(pyproj.Proj('EPSG:4326').definition_string()).crs.is_geographic                                                                                                                                                          
Out[7]: False

It seems like the extra towgs84=0,0,0 parameter in the definition_string causes the problem. Shouldn’t this be consistent? Or is this just another example of losing information when converting CRSes to proj4 strings?

pyproj version is 2.1.3.

Issue Analytics

State:
Created 4 years ago
Comments:7 (6 by maintainers)

Top GitHub Comments

1reaction

snowman2commented, Apr 23, 2019

Not a problem 👍. The solution is in master now if you want to give it a try.

0reactions

sfinkenscommented, Apr 23, 2019

@snowman2 Thanks for looking into it!

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