kai.reduce.dar
==============

.. py:module:: kai.reduce.dar


Attributes
----------

.. autoapisummary::

   kai.reduce.dar.p2
   kai.reduce.dar.module_dir


Functions
---------

.. autoapisummary::

   kai.reduce.dar.get_atm_conditions
   kai.reduce.dar.keckDARcoeffs
   kai.reduce.dar.download_koa_dat_files
   kai.reduce.dar.keckDARcoeffs_koa
   kai.reduce.dar.kaidar
   kai.reduce.dar.darPlusDistortion
   kai.reduce.dar.applyDAR
   kai.reduce.dar.removeDAR
   kai.reduce.dar.splitAtmosphereCFHT
   kai.reduce.dar.test_darPlusDistortion


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

.. py:data:: p2
   :value: False


.. py:data:: module_dir

.. py:function:: get_atm_conditions(year)

   
   Retrieve atmospheric conditions from CFHT archive website,
   then calls dar.splitAtmosphereCFHT() to separate the data
   by months.
















   ..
       !! processed by numpydoc !!

.. py:function:: keckDARcoeffs(lamda, year, month, day, hour, minute)

   
   Calculate the differential atmospheric refraction
   for two objects observed at Keck.

   Input:
   lamda -- Effective wavelength (microns) assumed to be the same for both
   year, month, day, hour, minute of observation (HST)

   Output:
   refA
   refB















   ..
       !! processed by numpydoc !!

.. py:function:: download_koa_dat_files(date_str, telescope_str, param_name, download_loc='./')

   
   Download the KOA atmospheric condition file for given date and
   specified parameter, and save at the download location


   :Parameters:

       **date_str** : str
           Date string for the night (e.g.: '20220525').

       **telescope_str** : str
           String to specify which Keck telescope's weather data to download.
           Can be 'k1' or 'k2'.

       **param_name** : str
           Name of the parameter to download the conditions table
           (e.g.: 'OutsideTemp')

       **download_loc** : str, default = './'
           Directory to store the downloaded atmospheric condition table file.














   ..
       !! processed by numpydoc !!

.. py:function:: keckDARcoeffs_koa(lamda, year, month, day, hour, minute, second, instrument=instruments.default_inst)

   
   Calculate the differential atmospheric refraction
   for two objects observed at Keck, using atmospheric conditions obtained
   via the KOA.


   :Parameters:

       **lamda** : float
           Effective wavelength (microns), assumed to be the same for both.

       **year** : int
           UTC year

       **month** : int
           UTC month

       **day** : int
           UTC date

       **hour** : int
           UTC hour

       **minute** : int
           UTC minute

       **second** : int, float
           UTC second

   :Returns:

       **refA** : float
           ..

       **refB** : float
           ..













   ..
       !! processed by numpydoc !!

.. py:function:: kaidar(fitsFile, instrument=instruments.default_inst, use_koa_weather=False)

   
   Use the FITS header to extract date, time, wavelength,
   elevation, and image orientation information. This is everything
   that is necessary to calculate the differential atmospheric
   refraction. The differential atmospheric refraction 
   is applicable only along the zenith direction of an image.
   This code calculates the predicted DAR using archived CFHT
   atmospheric data and the elevation and wavelength of the observations.
   Then the DAR correction is transformed into image coefficients that
   can be applied in image coordinates.
















   ..
       !! processed by numpydoc !!

.. py:function:: darPlusDistortion(inputFits, outputRoot, xgeoim=None, ygeoim=None, instrument=instruments.default_inst, use_koa_weather=False)

   
   Create lookup tables (stored as FITS files) that can be used
   to correct DAR. Optionally, the shifts due to DAR can be added
   to existing NIRC2 distortion lookup tables if the xgeoim/ygeoim
   input parameters are set.

   Inputs:
   inputFits - a NIRC2 image for which to determine the DAR correction
   outputRoot - the root name for the output. This will be used as the
       root name of two new images with names, <outputRoot>_x.fits and 
       <outputRoot>_y.fits.

   Optional Inputs:
   xgeoim/ygeoim - FITS images used in Drizzle distortion correction
       (lookup tables) will be modified to incorporate the DAR correction.
       The order of the correction is 1. distortion, 2. DAR.















   ..
       !! processed by numpydoc !!

.. py:function:: applyDAR(inputFits, spaceStarlist, plot=False, instrument=instruments.default_inst, plotdir='./')

   
   inputFits: (str) name of fits file associated with this starlist

   spaceStarlist: (astropy table) must include columns 'x0' and 'y0'.

   Input a starlist in x=RA (+x = west) and y=Dec (arcseconds) taken from
   space and introduce differential atmospheric refraction (DAR). The amount
   of DAR that is applied depends on the header information in the input fits
   file. The resulting output starlist should contain what was observed
   after the starlight passed through the atmosphere, but before the
   starlight passed through the telescope. Only achromatic DAR is 
   applied in this code.

   returns spaceStarlist with updated 'x0' and 'y0'















   ..
       !! processed by numpydoc !!

.. py:function:: removeDAR(inputFits, groundStarlist, plot=False, instrument=instruments.default_inst, plotdir='./')

   
   inputFits: (str) name of fits file associated with this starlist

   groundStarlist: (astropy table) must include columns 'x' and 'y'.

   The inverse of applyDAR(). Takes a starlist in x and y pixels taken from
   the ground and removes differential atmospheric refraction (DAR). The amount
   of DAR that is applied depends on the header information in the input fits
   file. The resulting output starlist should contain what would be observed above the atmosphere.
   Distortion should be applied before this function. Only achromatic DAR is 
   applied in this code.

   returns groundStarlist with updated 'x0' and 'y0'















   ..
       !! processed by numpydoc !!

.. py:function:: splitAtmosphereCFHT(year)

   
   Take an original archive file containing atmospheric parameters and
   split it up into seperate files for individual months. This makes
   later calls to calculate DAR parameters MUCH faster.
















   ..
       !! processed by numpydoc !!

.. py:function:: test_darPlusDistortion()