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 k r@| d |  j t j	 | d  9} n | d k rt j d d | |  j t j	 | d   } nJ | d k r´| d |  j t j	 | d  | } n t d j |    | S(   sÄ  Lomb-Scargle Periodogram

    This is a wrapper of ``scipy.signal.lombscargle`` for computation of the
    Lomb-Scargle periodogram. This is a relatively fast version of the naive
    O[N^2] algorithm, but cannot handle heteroskedastic errors.

    Parameters
    ----------
    t, y: array_like  (NOT astropy.Quantities)
        times, values, and errors of the data points. These should be
        broadcastable to the same shape.
    frequency : array_like
        frequencies (not angular frequencies) at which to calculate periodogram
    normalization : string (optional, default='standard')
        Normalization to use for the periodogram.
        Options are 'standard', 'model', 'log', or 'psd'.
    center_data : bool (optional, default=True)
        if True, pre-center the data by subtracting the weighted mean
        of the input data.

    Returns
    -------
    power : array_like
        Lomb-Scargle power associated with each frequency.
        Units of the result depend on the normalization.

    References
    ----------
    .. [1] M. Zechmeister and M. Kurster, A&A 496, 577-584 (2009)
    .. [2] W. Press et al, Numerical Recipes in C (2002)
    .. [3] Scargle, J.D. 1982, ApJ 263:835-853
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   ValueErrort   meant   lombscarglet   pit   sizeR   t   format(   t   tt   yt	   frequencyt   normalizationt   center_dataR   t   p(    (    sS   lib/python2.7/site-packages/astropy/stats/lombscargle/implementations/scipy_impl.pyt   lombscargle_scipy   s4    " %3)	(   t
   __future__R    R   t   numpyR
   t   TrueR   (    (    (    sS   lib/python2.7/site-packages/astropy/stats/lombscargle/implementations/scipy_impl.pyt   <module>   s   