France geocentric interpolation
May be used for transformation of NTF to/from ETR89 and WGS 84 as RGF93 may be considered equivalent to ETRS89 or WGS 84 within the accuracy of the transformation. See tfm codes 1054 and 15939. May be emulated using NTv2 method - see tfm code 15958.
Institut Geographique National (IGN) document NTG_88.pdf, "Grille de parametres de transformation de coordonnees". http://www.ign.fr
2010-03-30
Definition: OGC Well Known Text
GEOGCS["NTF", DATUM["Nouvelle_Triangulation_Francaise", SPHEROID["Clarke 1880 (IGN)",6378249.2,293.466021293627, AUTHORITY["EPSG","7011"]], AUTHORITY["EPSG","6275"]], PRIMEM["Greenwich",0, AUTHORITY["EPSG","8901"]], UNIT["degree",0.0174532925199433, AUTHORITY["EPSG","9122"]], AUTHORITY["EPSG","4275"]]
Definition: OGC Well Known Text 2 (2019)
GEOGCRS["NTF", DATUM["Nouvelle Triangulation Francaise", ELLIPSOID["Clarke 1880 (IGN)",6378249.2,293.466021293627, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], CS[ellipsoidal,2], AXIS["geodetic latitude (Lat)",north, ORDER[1], ANGLEUNIT["degree",0.0174532925199433]], AXIS["geodetic longitude (Lon)",east, ORDER[2], ANGLEUNIT["degree",0.0174532925199433]], USAGE[ SCOPE["Geodesy."], AREA["France - onshore - mainland and Corsica."], BBOX[41.31,-4.87,51.14,9.63]], ID["EPSG",4275]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "GeographicCRS", "name": "NTF", "datum": { "type": "GeodeticReferenceFrame", "name": "Nouvelle Triangulation Francaise", "ellipsoid": { "name": "Clarke 1880 (IGN)", "semi_major_axis": 6378249.2, "semi_minor_axis": 6356515 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "scope": "Geodesy.", "area": "France - onshore - mainland and Corsica.", "bbox": { "south_latitude": 41.31, "west_longitude": -4.87, "north_latitude": 51.14, "east_longitude": 9.63 }, "id": { "authority": "EPSG", "code": 4275 } }
Definition: GeoServer
4275=GEOGCS["NTF",DATUM["Nouvelle_Triangulation_Francaise",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.466021293627,AUTHORITY["EPSG","7011"]],AUTHORITY["EPSG","6275"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4275"]]
Definition: Mapnik
<?xml version="1.0" encoding="utf-8"?> <Map srs="+proj=longlat +ellps=clrk80ign +no_defs +type=crs"> <Layer srs="+proj=longlat +ellps=clrk80ign +no_defs +type=crs"> </Layer> </Map>
Definition: SQL (PostGIS)
INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 4275, 'EPSG', 4275, '+proj=longlat +ellps=clrk80ign +no_defs +type=crs', 'GEOGCS["NTF",DATUM["Nouvelle_Triangulation_Francaise",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.466021293627,AUTHORITY["EPSG","7011"]],AUTHORITY["EPSG","6275"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4275"]]');