Not sure whether to make it float or double by default
/*************************************************************************
doubles and floats are identical on AVR processors like the UNO where space
is tight. doubles avoid the roundoff errors that led to the fixed point mods
in https://github.com/adafruit/Adafruit-GPS-Library/pull/13, provided the
processor supports actual doubles like the SAMD series with more storage. The
total penalty for going all double is under a few hundred bytes / instance or
0 bytes / instance on an UNO. This typedef allows a switch to lower precision
to save some storage if needed. A float carries 23 bits of fractional
resolution, giving a resolution of at least 9 significant digits, thus 6
significant digits in the decimal place of an angular value like latitude, and
thus a resolution on earth of at least 110 mm. That's closer than GPS will
hit, and closer than needed for navigation, so floats can be used to save a
little storage.
**************************************************************************/
typedef double
nmea_float_t; ///< the type of variables to use for floating point
Rick Sellens