def start_date(self):
        """账户的起始交易日期(只在回测中使用)

        Raises:
            RuntimeWarning -- [description]

        Returns:
            [type] -- [description]
        """
        if self.start_==None:
            if len(self.time_index_max) > 0:
                return str(min(self.time_index_max))[0:10]
            else:
                print(
                    RuntimeWarning(
                        'QAACCOUNT: THIS ACCOUNT DOESNOT HAVE ANY TRADE'
                    )
                )
        else:
            return self.start_
def start_date ( self ) : if self . start_ == None : if len ( self . time_index_max ) > 0 : return str ( min ( self . time_index_max ) ) [ 0 : 10 ] else : print ( RuntimeWarning ( 'QAACCOUNT: THIS ACCOUNT DOESNOT HAVE ANY TRADE' ) ) else : return self . start_
账户的起始交易日期(只在回测中使用)

        Raises:
            RuntimeWarning -- [description]

        Returns:
            [type] -- [description]