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EPSG:27571

NTF (Paris) / Lambert zone I

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Center coordinates
552587.60 1215784.19

Projected bounds:
64398.20 1074408.53
1012167.98 1398560.88

WGS84 bounds:
-4.87 48.14
8.23 51.14

France mainland onshore north of 53.5 grads North (48°09'N).

Available transformations:

Selected transformation

NO DEFAULT TRANSFORMATION

Attributes

Unit: metre

Geodetic CRS: NTF (Paris)

Datum: Nouvelle Triangulation Francaise (Paris)

Ellipsoid: Clarke 1880 (IGN)

Prime meridian: Paris (['Paris', '2.5969213'] degree from Greenwich)

Data source: OGP

Revision date: 2001-11-06

Scope: Large and medium scale topographic mapping and engineering survey.

Remarks: Introduced 1972. Replaces NTF (Paris) / Lambert Nord France (code 27561).

Area of use: France mainland onshore north of 53.5 grads North (48°09'N).

Coordinate system: Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: m.

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Definition: Well Known Text (WKT)

PROJCS["NTF (Paris) / Lambert zone I",
    GEOGCS["NTF (Paris)",
        DATUM["Nouvelle_Triangulation_Francaise_Paris",
            SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,
                AUTHORITY["EPSG","7011"]],
            TOWGS84[-168,-60,320,0,0,0,0],
            AUTHORITY["EPSG","6807"]],
        PRIMEM["Paris",2.33722917,
            AUTHORITY["EPSG","8903"]],
        UNIT["grad",0.01570796326794897,
            AUTHORITY["EPSG","9105"]],
        AUTHORITY["EPSG","4807"]],
    PROJECTION["Lambert_Conformal_Conic_1SP"],
    PARAMETER["latitude_of_origin",55],
    PARAMETER["central_meridian",0],
    PARAMETER["scale_factor",0.999877341],
    PARAMETER["false_easting",600000],
    PARAMETER["false_northing",1200000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["X",EAST],
    AXIS["Y",NORTH],
    AUTHORITY["EPSG","27571"]]

PROJCS["NTF (Paris) / Lambert zone I",
    GEOGCS["NTF (Paris)",
        DATUM["Nouvelle_Triangulation_Francaise_Paris",
            SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,
                AUTHORITY["EPSG","7011"]],
            TOWGS84[-168,-60,320,0,0,0,0],
            AUTHORITY["EPSG","6807"]],
        PRIMEM["Paris",2.33722917,
            AUTHORITY["EPSG","8903"]],
        UNIT["grad",0.01570796326794897,
            AUTHORITY["EPSG","9105"]],
        AUTHORITY["EPSG","4807"]],
    PROJECTION["Lambert_Conformal_Conic_1SP"],
    PARAMETER["latitude_of_origin",55],
    PARAMETER["central_meridian",0],
    PARAMETER["scale_factor",0.999877341],
    PARAMETER["false_easting",600000],
    PARAMETER["false_northing",1200000],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    AXIS["X",EAST],
    AXIS["Y",NORTH],
    AUTHORITY["EPSG","27571"]]

Definition: ESRI WKT

PROJCS["NTF_Paris_Lambert_zone_I",GEOGCS["GCS_NTF_Paris",DATUM["D_NTF",SPHEROID["Clarke_1880_IGN",6378249.2,293.46602]],PRIMEM["Paris",2.33722917],UNIT["grad",0.01570796326794897]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["latitude_of_origin",55],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.999877341],PARAMETER["false_easting",600000],PARAMETER["false_northing",1200000],UNIT["Meter",1],PARAMETER["standard_parallel_1",55]]

Definition: PROJ.4

+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs

Definition: JavaScript (Proj4js) 

proj4.defs("EPSG:27571","+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs");

Definition: OGC GML

<?xml version="1.0" encoding="UTF-8"?>
 <gml:ProjectedCRS xmlns:epsg="urn:x-ogp:spec:schema-xsd:EPSG:1.0:dataset" xmlns:gml="http://www.opengis.net/gml/3.2" xmlns:xlink="http://www.w3.org/1999/xlink" gml:id="epsg-crs-27571">
   <gml:metaDataProperty>
      <epsg:CommonMetaData>
         <epsg:type>projected</epsg:type>
         <epsg:alias alias="NTF (Paris) / France I" code="1414" codeSpace="urn:ogc:def:naming-system:EPSG::7317" />
         <epsg:revisionDate>2001-11-06</epsg:revisionDate>
         <epsg:show>true</epsg:show>
         <epsg:isDeprecated>false</epsg:isDeprecated>
      </epsg:CommonMetaData>
   </gml:metaDataProperty>
   <gml:identifier codeSpace="OGP">urn:ogc:def:crs:EPSG::27571</gml:identifier>
   <gml:name>NTF (Paris) / Lambert zone I</gml:name>
   <gml:remarks>Introduced 1972. Replaces NTF (Paris) / Lambert Nord France (code 27561).</gml:remarks>
   <gml:domainOfValidity xlink:href="urn:ogc:def:area:EPSG::1731" />
   <gml:scope>Large and medium scale topographic mapping and engineering survey.</gml:scope>
   <gml:conversion xlink:href="urn:ogc:def:coordinateOperation:EPSG::18081" />
   <gml:baseGeodeticCRS xlink:href="urn:ogc:def:crs:EPSG::4807" />
   <gml:cartesianCS xlink:href="urn:ogc:def:cs:EPSG::4499" />
</gml:ProjectedCRS>

<?xml version="1.0" encoding="UTF-8"?>
 <gml:ProjectedCRS xmlns:epsg="urn:x-ogp:spec:schema-xsd:EPSG:1.0:dataset" xmlns:gml="http://www.opengis.net/gml/3.2" xmlns:xlink="http://www.w3.org/1999/xlink" gml:id="epsg-crs-27571">
   <gml:metaDataProperty>
      <epsg:CommonMetaData>
         <epsg:type>projected</epsg:type>
         <epsg:alias alias="NTF (Paris) / France I" code="1414" codeSpace="urn:ogc:def:naming-system:EPSG::7317" />
         <epsg:revisionDate>2001-11-06</epsg:revisionDate>
         <epsg:show>true</epsg:show>
         <epsg:isDeprecated>false</epsg:isDeprecated>
      </epsg:CommonMetaData>
   </gml:metaDataProperty>
   <gml:identifier codeSpace="OGP">urn:ogc:def:crs:EPSG::27571</gml:identifier>
   <gml:name>NTF (Paris) / Lambert zone I</gml:name>
   <gml:remarks>Introduced 1972. Replaces NTF (Paris) / Lambert Nord France (code 27561).</gml:remarks>
   <gml:domainOfValidity xlink:href="urn:ogc:def:area:EPSG::1731" />
   <gml:scope>Large and medium scale topographic mapping and engineering survey.</gml:scope>
   <gml:conversion xlink:href="urn:ogc:def:coordinateOperation:EPSG::18081" />
   <gml:baseGeodeticCRS xlink:href="urn:ogc:def:crs:EPSG::4807" />
   <gml:cartesianCS xlink:href="urn:ogc:def:cs:EPSG::4499" />
</gml:ProjectedCRS>

Definition: XML

<?xml version="1.0" encoding="UTF-8"?>
 <gml:ProjectedCRS gml:id="ogrcrs35319" xmlns:gml="http://www.opengis.net/gml/3.2">
  <gml:srsName>NTF (Paris) / Lambert zone I</gml:srsName>
  <gml:srsID>
    <gml:name gml:codeSpace="urn:ogc:def:crs:EPSG::">27571</gml:name>
  </gml:srsID>
  <gml:baseCRS>
    <gml:GeographicCRS gml:id="ogrcrs35320">
      <gml:srsName>NTF (Paris)</gml:srsName>
      <gml:srsID>
        <gml:name gml:codeSpace="urn:ogc:def:crs:EPSG::">4807</gml:name>
      </gml:srsID>
      <gml:usesEllipsoidalCS>
        <gml:EllipsoidalCS gml:id="ogrcrs35321">
          <gml:csName>ellipsoidal</gml:csName>
          <gml:csID>
            <gml:name gml:codeSpace="urn:ogc:def:cs:EPSG::">6402</gml:name>
          </gml:csID>
          <gml:usesAxis>
            <gml:CoordinateSystemAxis gml:id="ogrcrs35322" gml:uom="urn:ogc:def:uom:EPSG::9102">
              <gml:name>Geodetic latitude</gml:name>
              <gml:axisID>
                <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9901</gml:name>
              </gml:axisID>
              <gml:axisAbbrev>Lat</gml:axisAbbrev>
              <gml:axisDirection>north</gml:axisDirection>
            </gml:CoordinateSystemAxis>
          </gml:usesAxis>
          <gml:usesAxis>
            <gml:CoordinateSystemAxis gml:id="ogrcrs35323" gml:uom="urn:ogc:def:uom:EPSG::9102">
              <gml:name>Geodetic longitude</gml:name>
              <gml:axisID>
                <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9902</gml:name>
              </gml:axisID>
              <gml:axisAbbrev>Lon</gml:axisAbbrev>
              <gml:axisDirection>east</gml:axisDirection>
            </gml:CoordinateSystemAxis>
          </gml:usesAxis>
        </gml:EllipsoidalCS>
      </gml:usesEllipsoidalCS>
      <gml:usesGeodeticDatum>
        <gml:GeodeticDatum gml:id="ogrcrs35324">
          <gml:datumName>Nouvelle_Triangulation_Francaise_Paris</gml:datumName>
          <gml:datumID>
            <gml:name gml:codeSpace="urn:ogc:def:datum:EPSG::">6807</gml:name>
          </gml:datumID>
          <gml:usesPrimeMeridian>
            <gml:PrimeMeridian gml:id="ogrcrs35325">
              <gml:meridianName>Paris</gml:meridianName>
              <gml:meridianID>
                <gml:name gml:codeSpace="urn:ogc:def:meridian:EPSG::">8903</gml:name>
              </gml:meridianID>
              <gml:greenwichLongitude>
                <gml:angle gml:uom="urn:ogc:def:uom:EPSG::9102">2.33722917</gml:angle>
              </gml:greenwichLongitude>
            </gml:PrimeMeridian>
          </gml:usesPrimeMeridian>
          <gml:usesEllipsoid>
            <gml:Ellipsoid gml:id="ogrcrs35326">
              <gml:ellipsoidName>Clarke 1880 (IGN)</gml:ellipsoidName>
              <gml:ellipsoidID>
                <gml:name gml:codeSpace="urn:ogc:def:ellipsoid:EPSG::">7011</gml:name>
              </gml:ellipsoidID>
              <gml:semiMajorAxis gml:uom="urn:ogc:def:uom:EPSG::9001">6378249.2</gml:semiMajorAxis>
              <gml:secondDefiningParameter>
                <gml:inverseFlattening gml:uom="urn:ogc:def:uom:EPSG::9201">293.4660212936265</gml:inverseFlattening>
              </gml:secondDefiningParameter>
            </gml:Ellipsoid>
          </gml:usesEllipsoid>
        </gml:GeodeticDatum>
      </gml:usesGeodeticDatum>
    </gml:GeographicCRS>
  </gml:baseCRS>
  <gml:definedByConversion>
    <gml:Conversion gml:id="ogrcrs35327">
      <gml:usesMethod xlink:href="urn:ogc:def:method:EPSG::9801" />
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9102">49.50000000000001</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8801" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9102">0</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8802" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">0.999877341</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8805" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">600000</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8806" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">1200000</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8807" />
      </gml:usesParameterValue>
    </gml:Conversion>
  </gml:definedByConversion>
  <gml:usesCartesianCS>
    <gml:CartesianCS gml:id="ogrcrs35328">
      <gml:csName>Cartesian</gml:csName>
      <gml:csID>
        <gml:name gml:codeSpace="urn:ogc:def:cs:EPSG::">4400</gml:name>
      </gml:csID>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs35329" gml:uom="urn:ogc:def:uom:EPSG::9001">
          <gml:name>Easting</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9906</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>E</gml:axisAbbrev>
          <gml:axisDirection>east</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs35330" gml:uom="urn:ogc:def:uom:EPSG::9001">
          <gml:name>Northing</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9907</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>N</gml:axisAbbrev>
          <gml:axisDirection>north</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
    </gml:CartesianCS>
  </gml:usesCartesianCS>
</gml:ProjectedCRS>

<?xml version="1.0" encoding="UTF-8"?>
 <gml:ProjectedCRS gml:id="ogrcrs35319" xmlns:gml="http://www.opengis.net/gml/3.2">
  <gml:srsName>NTF (Paris) / Lambert zone I</gml:srsName>
  <gml:srsID>
    <gml:name gml:codeSpace="urn:ogc:def:crs:EPSG::">27571</gml:name>
  </gml:srsID>
  <gml:baseCRS>
    <gml:GeographicCRS gml:id="ogrcrs35320">
      <gml:srsName>NTF (Paris)</gml:srsName>
      <gml:srsID>
        <gml:name gml:codeSpace="urn:ogc:def:crs:EPSG::">4807</gml:name>
      </gml:srsID>
      <gml:usesEllipsoidalCS>
        <gml:EllipsoidalCS gml:id="ogrcrs35321">
          <gml:csName>ellipsoidal</gml:csName>
          <gml:csID>
            <gml:name gml:codeSpace="urn:ogc:def:cs:EPSG::">6402</gml:name>
          </gml:csID>
          <gml:usesAxis>
            <gml:CoordinateSystemAxis gml:id="ogrcrs35322" gml:uom="urn:ogc:def:uom:EPSG::9102">
              <gml:name>Geodetic latitude</gml:name>
              <gml:axisID>
                <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9901</gml:name>
              </gml:axisID>
              <gml:axisAbbrev>Lat</gml:axisAbbrev>
              <gml:axisDirection>north</gml:axisDirection>
            </gml:CoordinateSystemAxis>
          </gml:usesAxis>
          <gml:usesAxis>
            <gml:CoordinateSystemAxis gml:id="ogrcrs35323" gml:uom="urn:ogc:def:uom:EPSG::9102">
              <gml:name>Geodetic longitude</gml:name>
              <gml:axisID>
                <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9902</gml:name>
              </gml:axisID>
              <gml:axisAbbrev>Lon</gml:axisAbbrev>
              <gml:axisDirection>east</gml:axisDirection>
            </gml:CoordinateSystemAxis>
          </gml:usesAxis>
        </gml:EllipsoidalCS>
      </gml:usesEllipsoidalCS>
      <gml:usesGeodeticDatum>
        <gml:GeodeticDatum gml:id="ogrcrs35324">
          <gml:datumName>Nouvelle_Triangulation_Francaise_Paris</gml:datumName>
          <gml:datumID>
            <gml:name gml:codeSpace="urn:ogc:def:datum:EPSG::">6807</gml:name>
          </gml:datumID>
          <gml:usesPrimeMeridian>
            <gml:PrimeMeridian gml:id="ogrcrs35325">
              <gml:meridianName>Paris</gml:meridianName>
              <gml:meridianID>
                <gml:name gml:codeSpace="urn:ogc:def:meridian:EPSG::">8903</gml:name>
              </gml:meridianID>
              <gml:greenwichLongitude>
                <gml:angle gml:uom="urn:ogc:def:uom:EPSG::9102">2.33722917</gml:angle>
              </gml:greenwichLongitude>
            </gml:PrimeMeridian>
          </gml:usesPrimeMeridian>
          <gml:usesEllipsoid>
            <gml:Ellipsoid gml:id="ogrcrs35326">
              <gml:ellipsoidName>Clarke 1880 (IGN)</gml:ellipsoidName>
              <gml:ellipsoidID>
                <gml:name gml:codeSpace="urn:ogc:def:ellipsoid:EPSG::">7011</gml:name>
              </gml:ellipsoidID>
              <gml:semiMajorAxis gml:uom="urn:ogc:def:uom:EPSG::9001">6378249.2</gml:semiMajorAxis>
              <gml:secondDefiningParameter>
                <gml:inverseFlattening gml:uom="urn:ogc:def:uom:EPSG::9201">293.4660212936265</gml:inverseFlattening>
              </gml:secondDefiningParameter>
            </gml:Ellipsoid>
          </gml:usesEllipsoid>
        </gml:GeodeticDatum>
      </gml:usesGeodeticDatum>
    </gml:GeographicCRS>
  </gml:baseCRS>
  <gml:definedByConversion>
    <gml:Conversion gml:id="ogrcrs35327">
      <gml:usesMethod xlink:href="urn:ogc:def:method:EPSG::9801" />
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9102">49.50000000000001</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8801" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9102">0</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8802" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">0.999877341</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8805" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">600000</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8806" />
      </gml:usesParameterValue>
      <gml:usesParameterValue>
        <gml:value gml:uom="urn:ogc:def:uom:EPSG::9001">1200000</gml:value>
        <gml:valueOfParameter xlink:href="urn:ogc:def:parameter:EPSG::8807" />
      </gml:usesParameterValue>
    </gml:Conversion>
  </gml:definedByConversion>
  <gml:usesCartesianCS>
    <gml:CartesianCS gml:id="ogrcrs35328">
      <gml:csName>Cartesian</gml:csName>
      <gml:csID>
        <gml:name gml:codeSpace="urn:ogc:def:cs:EPSG::">4400</gml:name>
      </gml:csID>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs35329" gml:uom="urn:ogc:def:uom:EPSG::9001">
          <gml:name>Easting</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9906</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>E</gml:axisAbbrev>
          <gml:axisDirection>east</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs35330" gml:uom="urn:ogc:def:uom:EPSG::9001">
          <gml:name>Northing</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9907</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>N</gml:axisAbbrev>
          <gml:axisDirection>north</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
    </gml:CartesianCS>
  </gml:usesCartesianCS>
</gml:ProjectedCRS>

Definition: GeoServer

27571=PROJCS["NTF (Paris) / Lambert zone I",GEOGCS["NTF (Paris)",DATUM["Nouvelle_Triangulation_Francaise_Paris",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,AUTHORITY["EPSG","7011"]],TOWGS84[-168,-60,320,0,0,0,0],AUTHORITY["EPSG","6807"]],PRIMEM["Paris",2.33722917,AUTHORITY["EPSG","8903"]],UNIT["grad",0.01570796326794897,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4807"]],PROJECTION["Lambert_Conformal_Conic_1SP"],PARAMETER["latitude_of_origin",55],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.999877341],PARAMETER["false_easting",600000],PARAMETER["false_northing",1200000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","27571"]]

Definition: MapServer - MAPfile

PROJECTION
	"proj=lcc"
	"lat_1=49.50000000000001"
	"lat_0=49.50000000000001"
	"lon_0=0"
	"k_0=0.999877341"
	"x_0=600000"
	"y_0=1200000"
	"a=6378249.2"
	"b=6356515"
	"towgs84=-168,-60,320,0,0,0,0"
	"pm=paris"
	"units=m"
	"no_defs"
END

Definition: MapServer - Python

wkt = '''PROJCS["NTF (Paris) / Lambert zone I",GEOGCS["NTF (Paris)",DATUM["Nouvelle_Triangulation_Francaise_Paris",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,AUTHORITY["EPSG","7011"]],TOWGS84[-168,-60,320,0,0,0,0],AUTHORITY["EPSG","6807"]],PRIMEM["Paris",2.33722917,AUTHORITY["EPSG","8903"]],UNIT["grad",0.01570796326794897,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4807"]],PROJECTION["Lambert_Conformal_Conic_1SP"],PARAMETER["latitude_of_origin",55],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.999877341],PARAMETER["false_easting",600000],PARAMETER["false_northing",1200000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","27571"]]'''
m = mapObj('')
m.setWKTProjection(ref.ExportToWkt())
lyr = layerObj(m)
lyr.setWKTProjection(ref.ExportToWkt())

Definition: Mapnik

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs">
	<Layer srs="+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs">
	</Layer>
</Map>

Definition: Mapnik - Python

proj4 = '+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs'
m = Map(256,256,proj4)
lyr = Layer('Name',proj4)

Definition: SQL (PostGIS)

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 27571, 'EPSG', 27571, '+proj=lcc +lat_1=49.50000000000001 +lat_0=49.50000000000001 +lon_0=0 +k_0=0.999877341 +x_0=600000 +y_0=1200000 +a=6378249.2 +b=6356515 +towgs84=-168,-60,320,0,0,0,0 +pm=paris +units=m +no_defs ', 'PROJCS["NTF (Paris) / Lambert zone I",GEOGCS["NTF (Paris)",DATUM["Nouvelle_Triangulation_Francaise_Paris",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,AUTHORITY["EPSG","7011"]],TOWGS84[-168,-60,320,0,0,0,0],AUTHORITY["EPSG","6807"]],PRIMEM["Paris",2.33722917,AUTHORITY["EPSG","8903"]],UNIT["grad",0.01570796326794897,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4807"]],PROJECTION["Lambert_Conformal_Conic_1SP"],PARAMETER["latitude_of_origin",55],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.999877341],PARAMETER["false_easting",600000],PARAMETER["false_northing",1200000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","27571"]]');

Definition: OGC WKT

PROJCS["NTF (Paris) / Lambert zone I",GEOGCS["NTF (Paris)",DATUM["Nouvelle_Triangulation_Francaise_Paris",SPHEROID["Clarke 1880 (IGN)",6378249.2,293.4660212936265,AUTHORITY["EPSG","7011"]],TOWGS84[-168,-60,320,0,0,0,0],AUTHORITY["EPSG","6807"]],PRIMEM["Paris",2.33722917,AUTHORITY["EPSG","8903"]],UNIT["grad",0.01570796326794897,AUTHORITY["EPSG","9105"]],AUTHORITY["EPSG","4807"]],PROJECTION["Lambert_Conformal_Conic_1SP"],PARAMETER["latitude_of_origin",55],PARAMETER["central_meridian",0],PARAMETER["scale_factor",0.999877341],PARAMETER["false_easting",600000],PARAMETER["false_northing",1200000],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["X",EAST],AXIS["Y",NORTH],AUTHORITY["EPSG","27571"]]

Definition: USGS

[0, 0, (6378249.2, 6356515.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0), -1]