spinifex.image_tools.fits_tools
===============================

.. py:module:: spinifex.image_tools.fits_tools

.. autoapi-nested-parse::

   Predict / correct ionospheric RM in FITS images



Classes
-------

.. autoapisummary::

   spinifex.image_tools.fits_tools.FITSMetaData


Functions
---------

.. autoapisummary::

   spinifex.image_tools.fits_tools.correct_fits_images
   spinifex.image_tools.fits_tools.get_freq_from_fits
   spinifex.image_tools.fits_tools.get_integrated_rm_from_fits
   spinifex.image_tools.fits_tools.get_metadata_from_fits
   spinifex.image_tools.fits_tools.get_rm_from_fits


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

.. py:class:: FITSMetaData

   Bases: :py:obj:`NamedTuple`


   Metadata from a FITS file


   .. py:attribute:: duration
      :type:  astropy.time.TimeDelta

      Duration of observation



   .. py:attribute:: location
      :type:  astropy.coordinates.EarthLocation

      Location of observation



   .. py:attribute:: name
      :type:  str

      Name of FITS file as str



   .. py:attribute:: source
      :type:  astropy.coordinates.SkyCoord

      Target of observation



   .. py:attribute:: start_time
      :type:  astropy.time.Time

      Start time of obsrvation



.. py:function:: correct_fits_images(stokes_q_path: pathlib.Path, stokes_u_path: pathlib.Path, integrated_rm: spinifex.image_tools.image_tools.IntegratedRM, ext: int = 0, suffix: str = 'fr_corr') -> None

.. py:function:: get_freq_from_fits(fits_path: pathlib.Path) -> astropy.units.Quantity

   Get frequency array from FITS file

   Parameters
   ----------
   fits_path : Path
       Path to FITS file

   Returns
   -------
   u.Quantity
       Frequency array

   Raises
   ------
   FITSHeaderError
       If no spectral axis is found


.. py:function:: get_integrated_rm_from_fits(fits_path: pathlib.Path, timestep: astropy.units.Quantity = 15 * u.min, iono_model_name: str = 'ionex', magnetic_model_name: str = 'ppigrf', **iono_kwargs: Any) -> spinifex.image_tools.image_tools.IntegratedRM

   Computed the integrated RM effect following Van Eck (2021)

   Parameters
   ----------
   fits_path : Path
       Path to FITS file
   timestep : u.Quantity, optional
       Timestep to use for computing time-dependent RM, by default 15*u.min
   iono_model_name : str, optional
       ionospheric model name, by default "ionex". Must be a supported ionospheric model.
   magnetic_model_name : str, optional
       geomagnetic model name, by default "ppigrf". Must be a supported geomagnetic model.
   iono_kwargs : dict
       keyword arguments for the ionospheric model

   Returns
   -------
   IntegratedRM
       Integrated rotation measure object


.. py:function:: get_metadata_from_fits(fits_path: pathlib.Path) -> FITSMetaData

   Get metadata from a FITS file header

   Parameters
   ----------
   fits_path : Path
       FITS file

   Returns
   -------
   FitsMetaData
       FITS image metadata


.. py:function:: get_rm_from_fits(fits_path: pathlib.Path, timestep: astropy.units.Quantity = 15 * u.min, iono_model_name: str = 'ionex', magnetic_model_name: str = 'ppigrf', **iono_kwargs: Any) -> spinifex.get_rm.RM

   Get the ionospheric RM from a FITS file

   Parameters
   ----------
   fits_path : Path
       Path to FITS file
   timestep : u.Quantity, optional
       Time step to evaluate time-dependant RM, by default 15*u.min
   iono_model_name : str, optional
       ionospheric model name, by default "ionex". Must be a supported ionospheric model.
   magnetic_model_name : str, optional
       geomagnetic model name, by default "ppigrf". Must be a supported geomagnetic model.
   iono_kwargs : dict
       Keyword arguments for the ionospheric model

   Returns
   -------
   RM
       Rotation measure object