_GPSOPMODE returns the GPS operation mode as an integer.
0 = Manual. The GPS sensor is set to operate in 2-D or 3-D mode.
1 = Automatic. The GPS sensor can automatically switch between 2-D and 3-D modes.
The GPS internal variables require a GPS (internal or external) that supports the Windows Sensor Location APIs. Note that your GPS may not support all of the variables. If a value is not supported Windows will return "Element not found". Unless otherwise specified, the values returned are decimal numbers (for example, 38.735122).