'Compute the Lomb-Scargle model at the given frequency
Parameters
t : array_like or Quantity, length n_samples
times at which to compute the model
frequency : float
the frequency for the model
Returns
y : np.ndarray, length n_samples
The model fit corresponding to the input times'

def model(self, t, frequency):

    frequency = self._validate_frequency(frequency)
    t = self._validate_t(t)
    y_fit = periodic_fit(frequency=strip_units(frequency), t_fit=strip_units(t), center_data=self.center_data, fit_mean=self.fit_mean, nterms=self.nterms, *strip_units(self.t, self.y, self.dy))
    return (y_fit * get_unit(self.y))
