def __init__(self, tag, wing_param, OC):
'''
Constructor for wings based on lifting line theory
@param wing_geom : the wing geometry
@param Lref : Reference length for the moments computation
@param relaxFactor : relaxation factor for induced angles computation
@param stopCriteria : the stop criteria for the iterative method for computing the wing circulation.
'''
self.__tag = tag
self.__wing_param = wing_param
self.__OC = OC
self.__Lref = 0.
self.__Sref = 0.
self.__Lref_grad = None
self.__Sref_grad = None
self.__DLLMMesh = DLLMMesh(self)
self.__DLLMDirect = DLLMDirect(self)
self.__DLLMPost = DLLMPost(self)
self.__DLLMAdjoint = DLLMAdjoint(self)
self.set_OC(OC)
