:orphan:

:mod:`astrohack.combine`
========================

.. py:module:: astrohack.combine


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


Functions
~~~~~~~~~

.. autoapisummary::

   astrohack.combine.combine



.. function:: combine(image_name: str, combine_name: str = None, ant: Union[str, List[str]] = 'all', ddi: Union[int, List[int], str] = 'all', weighted: bool = False, parallel: bool = False, overwrite: bool = False) -> Union[astrohack.io.image_mds.AstrohackImageFile, None]

   Combine DDIs in a Holography image to increase SNR

   :param image_name: Input holography data file name. Accepted data format is the output from ``astrohack.holog.holog``
   :type image_name: str

   :param combine_name: Name of output file; File name will be appended with suffix *.combine.zarr*. Defaults to     *basename* of input file plus holography panel file suffix.
   :type combine_name: str, optional

   :param ant: List of antennas to be processed. None will use all antennas. Defaults to None, ex. ea25.
   :type ant: list or str, optional

   :param ddi: List of DDIs to be combined. None will use all DDIs. Defaults to None, ex. [0, ..., 8].
   :type ddi: list of int, optional

   :param weighted: Weight phases by the corresponding amplitudes.
   :type weighted: bool, optional

   :param parallel: Run in parallel. Defaults to False.
   :type parallel: bool, optional

   :param overwrite: Overwrite files on disk. Defaults to False.
   :type overwrite: bool, optional

   :return: Holography image object.
   :rtype: AstrohackImageFile

   .. _Description:
   **combine**

   Combine combines the amplitude and corrected_phase members of the selected DDIs in the input image file. Currently,     combine only supports the combination of these two quantities to avoid long regridding times. Hence, the output     image file (.combine.zarr file name) contains the combined amplitude and corrected_phase images, but the aperture     and beam images present in this file will be those present in the DDI with the lowest frequency.

   **AstrohackImageFile**

   Image object allows the user to access image data via compound dictionary keys with values, in order of depth,     `ant` -> `ddi`. The image object produced by combine is special because it will always contain a single DDI.    The image object also provides a `summary()` helper function to list available keys for each file.     An outline of the image object structure when produced by combine is show below:

   .. parsed-literal::
       image_mds =
           {
           ant_0:{
               ddi_n: image_ds,
           },
           ⋮
           ant_n: …
       }

   **Example Usage**

   .. parsed-literal::
       from astrohack.combine import combine

       combine(
           "astrohack_obs.image.zarr",
           ant = "ea25"
           weight = False
       )