spinifex.geometry.get_ipp
=========================

.. py:module:: spinifex.geometry.get_ipp

.. autoapi-nested-parse::

   Module for getting the Ionospheric Piercepoints



Classes
-------

.. autoapisummary::

   spinifex.geometry.get_ipp.IPP


Functions
---------

.. autoapisummary::

   spinifex.geometry.get_ipp._get_ipp_simple
   spinifex.geometry.get_ipp._make_dimensions_match
   spinifex.geometry.get_ipp.get_ipp_from_altaz
   spinifex.geometry.get_ipp.get_ipp_from_skycoord


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

.. py:class:: IPP

   Bases: :py:obj:`NamedTuple`


   Ionospheric Piercepoints


   .. py:attribute:: airmass
      :type:  numpy.typing.NDArray[numpy.float64]

      airmass factor to convert to slant values



   .. py:attribute:: altaz
      :type:  astropy.coordinates.AltAz

      azimuth elevation



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

      location of the piercepoints, dimension: times x altitudes. All altitudes are assumed to be equal



   .. py:attribute:: los
      :type:  numpy.typing.NDArray[numpy.float64]

      Line of sight direction in ITRS coordinates, normalized



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

      Observer Location



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

      array of times



.. py:function:: _get_ipp_simple(height_array: astropy.units.Quantity, loc: astropy.coordinates.EarthLocation, los_dir: astropy.coordinates.SkyCoord) -> tuple[list[astropy.units.Quantity], numpy.typing.NDArray[numpy.float64]]

   helper function to calculate ionospheric piercepoints using a simple spherical earth model

   .. code-block::

       |loc + alphas * los_dir| = R_earth + height_array

   solve for alphas using abc formula

   Parameters
   ----------
   height_array : u.Quantity
       array of altitudes
   loc : EarthLocation
       observer location
   los_dir : ITRS
       line of sight, unit vector

   Returns
   -------
   tuple(list[u.Quantity], NDArray)
       ipp.x, ipp.y, ipp.z positions, airmass


.. py:function:: _make_dimensions_match(altaz: astropy.coordinates.AltAz) -> astropy.coordinates.AltAz

   Helper function to change time dimensions suchthat they correspond to the altaz dimension

   Parameters
   ----------
   altaz : AltAz
       the altaz object

   Returns
   -------
   AltAz
       altaz object with matching obstime dimension

   Raises
   ------
   NotImplementedError
       multiple times with different shape than altaz is not implemented yet


.. py:function:: get_ipp_from_altaz(loc: astropy.coordinates.EarthLocation, altaz: astropy.coordinates.AltAz, height_array: astropy.units.Quantity) -> IPP

   get ionospheric piercepoints from azimuth elevations

   Parameters
   ----------
   loc : EarthLocation
       observer location
   altaz : AltAz
       azimuth and elevations for all times
   height_array : u.Quantity
       array of altitudes

   Returns
   -------
   IPP
       ionospheric piercepoints


.. py:function:: get_ipp_from_skycoord(loc: astropy.coordinates.EarthLocation, times: astropy.time.Time, source: astropy.coordinates.SkyCoord, height_array: astropy.units.Quantity) -> IPP

   Get ionospheric piercepoints

   Parameters
   ----------
   loc : EarthLocation
       observer location
   times : Time
       observation times
   source : SkyCoord
       source location
   height_array : u.Quantity
       array of altitudes

   Returns
   -------
   IPP
       Ionospheric piercepoints