EPSG

EPSG guidance note #7-2, http://www.epsg.org, after Institut de Geomatica; Barcelona.

2011-07-10

Note: These formulas have been transcribed from EPSG Guidance Note #7-2. Users are encouraged to use that document rather than the text which follows as reference because limitations in the transcription will be avoided. The polynomial expressions are: dLat seconds = A0 + (A1*lat) + (A2*lon) + (A3*H) dLon seconds = B00 + B0 + (B1*lat) + (B2*lon) + (B3*H) where latitude lat and longitude lon are in decimal degrees referred to the Madrid 1870 (Madrid) geographic coordinate reference system and H is gravity-related height in metres. B00 is the longitude (in seconds) of the Madrid meridian measured from the Greenwich meridian; it is the value to be applied to a longitude relative to the Madrid meridian to transform it to a longitude relative to the Greenwich meridan. The results of these expressions are applied through the formulae: Lat(ED50) = Lat(M1870(M)) + dLat and Lon(ED50) = Lon(M1870(M)) + dLon.

Input point coordinate system: Madrid 1870 (Madrid) (geographic 3D) Latitude = 42 deg 38 min 52.77 sec N = 42.647992 degrees Longitude = 3 deg 39 min 34.57 sec E of Madrid = +3.659603 degrees from the Madrid meridian. Height = 0 m For the north zone transformation: A0 = 11.328779 A1 = -0.1674 A2 = -0.03852 A3 = 0.0000379 B00 = -13276.58 B0 = 2.5079425 B1 = 0.08352 B2 = -0.00864 B3 = -0.0000038 dLat = +4.05 seconds Then ED50 latitude = 42 deg 38 min 52.77 sec N + 4.05sec = 42 deg 38 min 56.82 sec N dLon = -13270.54 seconds = -3 deg 41 min 10.54 sec Then ED50 longitude = 3 deg 39 min 34.57 sec E - 3 deg 41 min 10.54 sec = 0 deg 01 min 35.97 sec W of Greenwich.