The value is stored internally in radians, but is converted to and
from a degrees string for access. Some example input formats are:
"22:19:23.2", "22 19 23.2", "22:19.387", "22.32311", "N22.32311",
"-45.6", "S45.6". As indicated, the sign of the latitude can
optionally be indicated using characters "N" and "S" in place of the
usual "" and "-". When converting the stored value to a string, the
format "[s]dd:mm:ss.ss" is used, when "[s]" is "N" or "S".