The fors_resample recipe
===============================================================

.. data:: fors_resample

Synopsis
--------

Resample input spectra at constant wavelength step

Description
-----------

This recipe is used to resample at constant wavelength step spatially
rectified spectra. The input frames are produced using either the recipe
fors_extract_slits in the case of MOS/MXU multi slit exposures, or the
recipes fors_remove_bias and fors_flatfield in the case of LSS or long-slit
like MOS/MXU data. Only in case of LSS or LSS-like data the SLIT_LOCATION
table is required in input. Please refer to the FORS Pipeline User's Manual
for more details.


In the table below the MXU acronym can also be read as MOS and LSS, SCI
can be read as STD, and SCIENCE as STANDARD.


Input files
^^^^^^^^^^^^
::

  DO category:               Type:       Explanation:         Required:
  LAMP_UNBIAS_MXU
  or SCIENCE_UNBIAS_MXU
  or SCIENCE_UNFLAT_MXU
  or RECTIFIED_LAMP_MXU
  or RECTIFIED_ALL_SCI_MXU
  or RECTIFIED_SCI_MXU
  or RECTIFIED_SKY_SCI_MXU   Calib       Frame to resample       Y
  DISP_COEFF_MXU
  or DISP_COEFF_SCI_MXU      Calib       Dispersion coefficients Y
  SLIT_LOCATION_MXU          Calib       Slit location table     Y
  GRISM_TABLE                Calib       Grism table             .


Output files
^^^^^^^^^^^^
::

  DO category:               Data type:  Explanation:
  MAPPED_LAMP_MXU
  or MAPPED_ALL_SCI_MXU
  or MAPPED_SCI_MXU
  or MAPPED_SKY_SCI_MXU      FITS image  Resampled spectra


Constructor
-----------

.. method:: cpl.Recipe("fors_resample")
   :noindex:

   Create an object for the recipe fors_resample.

::

   import cpl
   fors_resample = cpl.Recipe("fors_resample")

Parameters
----------

.. py:attribute:: fors_resample.param.dispersion

    Expected spectral dispersion (Angstrom/pixel) (float; default: 0.0) [default=0.0].
.. py:attribute:: fors_resample.param.startwavelength

    Start wavelength in spectral extraction (float; default: 0.0) [default=0.0].
.. py:attribute:: fors_resample.param.endwavelength

    End wavelength in spectral extraction (float; default: 0.0) [default=0.0].
.. py:attribute:: fors_resample.param.flux

    Apply flux conservation (bool; default: True) [default=True].


The following code snippet shows the default settings for the available 
parameters.

::

   import cpl
   fors_resample = cpl.Recipe("fors_resample")

   fors_resample.param.dispersion = 0.0
   fors_resample.param.startwavelength = 0.0
   fors_resample.param.endwavelength = 0.0
   fors_resample.param.flux = True


You may also set or overwrite some or all parameters by the recipe 
parameter `param`, as shown in the following example:

::

   import cpl
   fors_resample = cpl.Recipe("fors_resample")
   [...]
   res = fors_resample( ..., param = {"dispersion":0.0, "startwavelength":0.0})


.. seealso:: `cpl.Recipe <https://packages.python.org/python-cpl/recipe.html>`_
   for more information about the recipe object.

Bug reports
-----------

Please report any problems to `Carlo Izzo <usd-help@eso.org>`_. Alternatively, you may 
send a report to the `ESO User Support Department <usd-help@eso.org>`_.

Copyright
---------

This file is currently part of the FORS Instrument Pipeline
Copyright (C) 2002-2010 European Southern Observatory

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA


.. codeauthor:: Carlo Izzo <usd-help@eso.org>