code: def set_model(self, f0, A, model='trigonometric'):
          
          self.f0 = f0
          self.y_clean, vary = trigonometric_model(self.t, f0, A)
          # y_clean is normalized to have unit standard deviation
          self.y_clean = self.y_clean/np.sqrt(vary)
docs: See also
          --------
          trigonometric_model