Reykjavik (1900) datum, prerequisites #721
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…ort of the Reykjavik 1900 datum (Iceland)
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Danish (Andræ) ellipsoid, and Copenhagen meridian introduced in support of the Reykjavik 1900 datum (Iceland).
The magnitude of the Danish (1876) ellipsoid was originally given in French toise (fathoms) - the Andræ ellipsoid already in PROJ seems to have been transformed to meters using a conversion factor for German fathoms.
This version, based on a French conversion factor of 1.94903631 m/toise, corresponds to the official value for the semimajor axis used by the Icelandic NMA, Landmælingar Íslands, LMI (Guðmundur Valsson, LMI, pers. comm. 2017-12-15).
This value deviates by approximately one centimeter, compared to the truncated value of 6377019.27 m, given in the EPSG:7051 record.