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How do I convert 52°52'16.9"N 0°46'43.5"W to DMS (Degress Minutes Seconds) to DEG ((decimal) Degrees) in Lua?

There is a great explanation of how to do this with 48°12'30" N 16°22'28" E or Zurich: dms: 47°21'7" N 8°30'37" E At How to convert GPS coordinates to decimal in Lua? However, I cannot work out how to trap to include the decimal value, as in 52°52'16.9"N 0°46'43.5"W.

Solution

  • Use the \' to escape the sequence:

    local dms = '52°52\'16.9"N'
print (dms)
local degrees, minutes, seconds, direction = dms:match('(%d+)%D+(%d+)%D+(%d+%.?%d*)%D*([NSEW])')
print (degrees, minutes, seconds, direction)
local decimal = tonumber(degrees) + tonumber(minutes) / 60 + tonumber(seconds) / 60^2

if direction == 'S' or direction == 'W' then
    print (-decimal)
else
    print (decimal) -- positive
end

    52°52'16.9"N
52  52  16.9    N
52.871361111111