def __init__(self, **params):
self.params = Params(**params)
self.__indexes__ = __Entities__(nvl(self.params.signal_index, -1),
nvl(self.params.annotation_index, -1),
nvl(self.params.time_index, -1))
self.__headers__ = None
self.__data_vector__ = None
if not is_positive(self.params.time_index):
self.__data_source__ = NumericalFileDataSource(**params)
else:
#if there is separate column of time all data are loaded
#in string format, getDataVector method do further processing
#and change into numerical values
self.__data_source__ = TextFileDataSource(**params)
