EPSG:4901 — ATF (Paris)

Geographic 2D · France - mainland onshore

Export Formats

OGC WKT

GEOGCS[
    "ATF (Paris)",
    DATUM[
        "Ancienne_Triangulation_Francaise_Paris",
        SPHEROID["Plessis 1817",6376523,308.64,AUTHORITY["EPSG","7027"]],
        AUTHORITY["EPSG","6901"]
    ],
    PRIMEM["Paris RGS",2.33720833333333,AUTHORITY["EPSG","8914"]],
    UNIT["grad",0.0157079632679489,AUTHORITY["EPSG","9105"]],
    AUTHORITY["EPSG","4901"]
]

WKT2

GEOGCRS[
    "ATF (Paris)",
    DATUM[
        "Ancienne Triangulation Francaise (Paris)",
        ELLIPSOID[
            "Plessis 1817",
            6376523,
            308.64,
            LENGTHUNIT["metre",1,ID["EPSG",9001]],
            ID["EPSG",7027]
        ],
        ID["EPSG",6901]
    ],
    PRIMEM[
        "Paris RGS",
        2.337208333,
        ANGLEUNIT["degree",0.0174532925199433,ID["EPSG",9102]],
        ID["EPSG",8914]
    ],
    CS[ellipsoidal,2,ID["EPSG",6403]],
    AXIS["Geodetic latitude (Lat)",north],
    AXIS["Geodetic longitude (Lon)",east],
    ANGLEUNIT["grad",0.015707963267949,ID["EPSG",9105]],
    ID["EPSG",4901]
]

PROJ.4

+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs

Proj4js

How to add a projection to Proj4js? →

proj4.defs("EPSG:4901", "+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs");

JSON

{
  "type": "CoordinateReferenceSystem",
  "code": 4901,
  "name": "ATF (Paris)",
  "kind": "geographic 2D",
  "area": "France - mainland onshore",
  "unit": "grad",
  "bbox": [
    42.33,
    -4.87,
    51.14,
    8.23
  ],
  "proj4": "+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs"
}

PostGIS

How to add a projection to PostGIS? →

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (4901, 'EPSG', 4901, '+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs', 'GEOGCS["ATF (Paris)",DATUM["Ancienne_Triangulation_Francaise_Paris",SPHEROID["Plessis 1817",6376523,308.64,AUTHORITY["EPSG","7027"]],AUTHORITY["EPSG","6901"]],PRIMEM["Paris RGS",2.33720833333333,AUTHORITY["EPSG","8914"]],UNIT["grad",0.0157079632679489,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4901"]]');

MapServer

How to add a projection to MapServer? →

PROJECTION
  "+proj=longlat"
  "+a=6376523"
  "+rf=308.64"
  "+pm=2.33720833333333"
  "+no_defs"
  "+type=crs"
END

GeoServer

How to add a projection to GeoServer? →

4901=GEOGCS["ATF (Paris)",DATUM["Ancienne_Triangulation_Francaise_Paris",SPHEROID["Plessis 1817",6376523,308.64,AUTHORITY["EPSG","7027"]],AUTHORITY["EPSG","6901"]],PRIMEM["Paris RGS",2.33720833333333,AUTHORITY["EPSG","8914"]],UNIT["grad",0.0157079632679489,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4901"]]

Other CRS using Ancienne Triangulation Francaise (Paris)

Frequently Asked Questions

How do I add EPSG:4901 to GeoServer?

Add the following definition to your GeoServer configuration:

4901=GEOGCS["ATF (Paris)",DATUM["Ancienne_Triangulation_Francaise_Paris",SPHEROID["Plessis 1817",6376523,308.64,AUTHORITY["EPSG","7027"]],AUTHORITY["EPSG","6901"]],PRIMEM["Paris RGS",2.33720833333333,AUTHORITY["EPSG","8914"]],UNIT["grad",0.0157079632679489,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4901"]]

Read the full GeoServer guide →

How do I add EPSG:4901 to PostGIS?

Add the following definition to your PostGIS configuration:

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (4901, 'EPSG', 4901, '+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs', 'GEOGCS["ATF (Paris)",DATUM["Ancienne_Triangulation_Francaise_Paris",SPHEROID["Plessis 1817",6376523,308.64,AUTHORITY["EPSG","7027"]],AUTHORITY["EPSG","6901"]],PRIMEM["Paris RGS",2.33720833333333,AUTHORITY["EPSG","8914"]],UNIT["grad",0.0157079632679489,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4901"]]');

Read the full PostGIS guide →

How do I add EPSG:4901 to MapServer?

Add the following definition to your MapServer configuration:

PROJECTION
  "+proj=longlat"
  "+a=6376523"
  "+rf=308.64"
  "+pm=2.33720833333333"
  "+no_defs"
  "+type=crs"
END

Read the full MapServer guide →

How do I use EPSG:4901 with Proj4js?

Add the following definition to your Proj4js configuration:

proj4.defs("EPSG:4901", "+proj=longlat +a=6376523 +rf=308.64 +pm=2.33720833333333 +no_defs +type=crs");

Read the full Proj4js guide →