Incorrect reading of magnetometer

[seerichard]

According to the datasheet, the line:

mag_x, mag_y, mag_z = mag

should be:

mag_x, mag_z, mag_y = mag

Unlike the accelerometer which is read x,y,z, the magnetometer is read as x,z,y. I have tested this and it seems to check out. It also aligns with the Arduino code Adafruit has provided for this board.