def _getAction(subAssignments):

	"""
	Given a group of assignments with same odID, find if this group is stationary/vertical/move.  Each will be treated differently in cesium and folium.

	Parameters
	----------
	subAssignments: :ref:`Assignments`
		An assignment dataframe with the same odID

	Return
	------
	string
		An enumerate string, out put can be 'stationary'/'vertical'/'move'
	"""

	# if it is static or vertical, there should (must) be one row for correspondence `odID`
	if (len(subAssignments) == 1):
		if (subAssignments.iloc[0]['startLat'] == subAssignments.iloc[0]['endLat']
			and subAssignments.iloc[0]['startLon'] == subAssignments.iloc[0]['endLon']
			and subAssignments.iloc[0]['startAltMeters'] == subAssignments.iloc[0]['endAltMeters']):
			action = "stationary"
		elif (subAssignments.iloc[0]['startLat'] == subAssignments.iloc[0]['endLat']
			and subAssignments.iloc[0]['startLon'] == subAssignments.iloc[0]['endLon']
			and subAssignments.iloc[0]['startAltMeters'] != subAssignments.iloc[0]['endAltMeters']):
			action = "vertical"
		else:
			action = "move"
	else:
		action = "move"

	return action