# GPS coordinates

Header header
string item # the name of the item
bool isnull
# Latitude [degrees]. Positive is north of equator; negative is south.
float64 latitude

# Longitude [degrees]. Positive is east of prime meridian; negative is west.
float64 longitude

# Altitude [m]. Positive is above the WGS 84 ellipsoid
# (quiet NaN if no altitude is available).
float64 altitude