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excelgpscoordinatesdegreesgarmin

Convert Degree Minutes to decimal degrees

I have location points collected from a garmin device stored in an excel sheet in Degree Minutes format --- W00208.172,N1046.977 How can I convert it to either Decimal Degrees or Degrees Minutes seconds Format ?

Solution

  • The range of longitude (E or W) is -180 to 180, so 3 digits The range of latitude (N or S) is -90 to 90, so 2 digits

    Take "W00208.172", take the first 3 digits and store it to degress:

    deg = 002 Then take the rest as decimal minutes:

    min = 08.172

    Now convert to decimal degrees (DEG):

    decDegrees = deg + min / 60.0

    Same for latitude: except that degrees are now only 2 digits N1046.977: Take 10 degrees, and 46.977 minutes.

    For both think if you want to keep the "W" symbol:
    Often it is better to mutiply with -1 in case of of "W" or "S", do this as last step in your conversion! Negative decimal degrees means W (for longitude) or S (for latitude).

    For your provides coordinates that means:
    lat: North 10046.977 = 10 + 46.977 / 60 = 10.78295;
    lon: (2 + 8.172 / 60) * -1 = -2.1362;
    so that location should be in Burkina Faso, 15m near a road (= plausible) 5,52 km south east east of Dununuai