def smooth_lowess(self, smoothing_parameter = None,
number_of_iterations=None, differential_order = 0):
'''Lowess data smoothing'''
smoother = SmoothingLowess(self)
smoother.differential_order = differential_order
if smoothing_parameter is not None:
smoother.smoothing_parameter = smoothing_parameter
if number_of_iterations is not None:
smoother.number_of_iterations = number_of_iterations
if smoothing_parameter is None or smoothing_parameter is None:
smoother.edit_traits()
else:
smoother.apply()
