healpix_analyse.powerspectra
============================

.. py:module:: healpix_analyse.powerspectra


Attributes
----------

.. autoapisummary::

   healpix_analyse.powerspectra.ArrayLike


Functions
---------

.. autoapisummary::

   healpix_analyse.powerspectra.powerspectra


Module Contents
---------------

.. py:data:: ArrayLike

.. py:function:: powerspectra(cell_ids, level, data, ltf=None, ellipsoid: str = 'sphere', method: str = 'fft', indexing_scheme: str = '2D_array', dx=1.0, cross=None, plot_2D_fft=False)

   Compute the isotropic 1D power spectrum of a 2D HEALPix field.

   :Parameters: * **data** (:py:class:`ndarray (ny`, :py:class:`nx)`) -- Input 2D field.
                * **dx** (:py:class:`float`) -- Pixel size in the same spatial unit as desired frequency inverse.
                  If dx is in meters, returned frequencies are in m^-1 (cycles per meter).

   :returns: * **f_centers** (:py:class:`ndarray`) -- Array of radial spatial frequencies (cycles per unit length), e.g., m^-1 if dx is in meters.
             * **Pk** (:py:class:`ndarray`) -- Azimuthally averaged power spectrum over radial frequency bins (arbitrary units unless you add a normalization).