nmhpgn.las nmhpgn.los
Accuracy 67% confidence level. Uses NADCON method which expects longitudes positive west; EPSG GeogCRSs NAD83 (code 4269) and NAD83(HARN) (code 4152) have longitudes positive east. May be taken as approximate transformation NAD83-WGS 84 - see code 1726.
US Coast & Geodetic Survey www.ngs.noaa.gov NADCON readme file
2023-01-17
US survey foot
EPSG
National Geodetic Survey
2016-07-13
Engineering survey, topographic mapping.
State law defines system in US survey feet. Federal definition is metric - see code 26981. For applications with an accuracy of better than 3 feet, replaced by NAD83(HARN) / SPCS.
Cartesian 2D CS. Axes: easting, northing (X,Y). Orientations: east, north. UoM: ftUS.
Definition: OGC Well Known Text 2 (2019)
BOUNDCRS[ SOURCECRS[ PROJCRS["NAD83 / Louisiana North (ftUS)", BASEGEOGCRS["NAD83", DATUM["North American Datum 1983", ELLIPSOID["GRS 1980",6378137,298.257222101, LENGTHUNIT["metre",1]]], PRIMEM["Greenwich",0, ANGLEUNIT["degree",0.0174532925199433]], ID["EPSG",4269]], CONVERSION["SPCS83 Louisiana North zone (US survey foot)", METHOD["Lambert Conic Conformal (2SP)", ID["EPSG",9802]], PARAMETER["Latitude of false origin",30.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8821]], PARAMETER["Longitude of false origin",-92.5, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8822]], PARAMETER["Latitude of 1st standard parallel",32.6666666666667, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8823]], PARAMETER["Latitude of 2nd standard parallel",31.1666666666667, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8824]], PARAMETER["Easting at false origin",3280833.3333, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8826]], PARAMETER["Northing at false origin",0, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",8827]]], CS[Cartesian,2], AXIS["easting (X)",east, ORDER[1], LENGTHUNIT["US survey foot",0.304800609601219]], AXIS["northing (Y)",north, ORDER[2], LENGTHUNIT["US survey foot",0.304800609601219]], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["United States (USA) - Louisiana - counties of Avoyelles; Bienville; Bossier; Caddo; Caldwell; Catahoula; Claiborne; Concordia; De Soto; East Carroll; Franklin; Grant; Jackson; La Salle; Lincoln; Madison; Morehouse; Natchitoches; Ouachita; Rapides; Red River; Richland; Sabine; Tensas; Union; Vernon; Webster; West Carroll; Winn."], BBOX[30.85,-94.05,33.03,-90.86]], ID["EPSG",3451]]], TARGETCRS[ GEOGCRS["NAD83(HARN)", DATUM["NAD83 (High Accuracy Reference Network)", ELLIPSOID["GRS 1980",6378137,298.257222101, 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["Horizontal component of 3D system."], AREA["American Samoa - onshore - Tutuila, Aunu'u, Ofu, Olesega, Ta'u and Rose islands. Guam - onshore. Northern Mariana Islands - onshore. Puerto Rico - onshore. United States (USA) - onshore Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, West Virginia, Wisconsin and Wyoming; offshore Gulf of Mexico continental shelf (GoM OCS). US Virgin Islands - onshore."], BBOX[-14.59,144.58,71.4,-64.51]], ID["EPSG",4152]]], ABRIDGEDTRANSFORMATION["NAD83 to NAD83(HARN) (18)", METHOD["NADCON", ID["EPSG",9613]], PARAMETERFILE["Latitude difference file","nmhpgn.las"], PARAMETERFILE["Longitude difference file","nmhpgn.los"], USAGE[ SCOPE["Geodesy."], AREA["United States (USA) - New Mexico."], BBOX[31.33,-109.06,37,-102.99]], ID["EPSG",1491], REMARK["Accuracy 67% confidence level. Uses NADCON method which expects longitudes positive west; EPSG GeogCRSs NAD83 (code 4269) and NAD83(HARN) (code 4152) have longitudes positive east. May be taken as approximate transformation NAD83-WGS 84 - see code 1726."]]]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "BoundCRS", "source_crs": { "type": "ProjectedCRS", "name": "NAD83 / Louisiana North (ftUS)", "base_crs": { "name": "NAD83", "datum": { "type": "GeodeticReferenceFrame", "name": "North American Datum 1983", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4269 } }, "conversion": { "name": "SPCS83 Louisiana North zone (US survey foot)", "method": { "name": "Lambert Conic Conformal (2SP)", "id": { "authority": "EPSG", "code": 9802 } }, "parameters": [ { "name": "Latitude of false origin", "value": 30.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8821 } }, { "name": "Longitude of false origin", "value": -92.5, "unit": "degree", "id": { "authority": "EPSG", "code": 8822 } }, { "name": "Latitude of 1st standard parallel", "value": 32.6666666666667, "unit": "degree", "id": { "authority": "EPSG", "code": 8823 } }, { "name": "Latitude of 2nd standard parallel", "value": 31.1666666666667, "unit": "degree", "id": { "authority": "EPSG", "code": 8824 } }, { "name": "Easting at false origin", "value": 3280833.3333, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8826 } }, { "name": "Northing at false origin", "value": 0, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 }, "id": { "authority": "EPSG", "code": 8827 } } ] }, "coordinate_system": { "subtype": "Cartesian", "axis": [ { "name": "Easting", "abbreviation": "X", "direction": "east", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } }, { "name": "Northing", "abbreviation": "Y", "direction": "north", "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } } ] }, "id": { "authority": "EPSG", "code": 3451 } }, "target_crs": { "type": "GeographicCRS", "name": "NAD83(HARN)", "datum": { "type": "GeodeticReferenceFrame", "name": "NAD83 (High Accuracy Reference Network)", "ellipsoid": { "name": "GRS 1980", "semi_major_axis": 6378137, "inverse_flattening": 298.257222101 } }, "coordinate_system": { "subtype": "ellipsoidal", "axis": [ { "name": "Geodetic latitude", "abbreviation": "Lat", "direction": "north", "unit": "degree" }, { "name": "Geodetic longitude", "abbreviation": "Lon", "direction": "east", "unit": "degree" } ] }, "id": { "authority": "EPSG", "code": 4152 } }, "transformation": { "name": "NAD83 to NAD83(HARN) (18)", "method": { "name": "NADCON", "id": { "authority": "EPSG", "code": 9613 } }, "parameters": [ { "name": "Latitude difference file", "value": "nmhpgn.las", "id": { "authority": "EPSG", "code": 8657 } }, { "name": "Longitude difference file", "value": "nmhpgn.los", "id": { "authority": "EPSG", "code": 8658 } } ], "id": { "authority": "EPSG", "code": 1491 } } }
Definition: Mapnik
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