Source code for mangadap.par.absorptionindexdb

# Licensed under a 3-clause BSD style license - see LICENSE.rst
# -*- coding: utf-8 -*-
Container class for the database of absorption-line indices to measure.

Class usage examples

Absorption-line index databases are defined using SDSS parameter files. To
define a database, you can use one of the default set of available
absorption-line index databases::

    from mangadap.par.absorptionindexdb import AbsorptionIndexDB
    absdb = AbsorptionIndexDB.from_key('LICKINDX')

The above call uses the :func:`AbsorptionIndexDB.from_key` method to
define the database using its keyword and the database provided with
the MaNGA DAP source distribution. You can also define the database
directly for an SDSS-style parameter file::

    from mangadap.par.absorptionindexdb import AbsorptionIndexDB
    absdb = AbsorptionIndexDB('/path/to/absorption/index/database/myabs.par')

The above will read the file and set the database keyword to
'MYABS' (i.e., the capitalized root name of the ``*.par`` file).
See :ref:`spectralindices` for the format of the parameter file.
Revision history

    | **18 Mar 2016**: Original implementation by K. Westfall (KBW)
    | **11 May 2016**: (KBW) Switch to using `pydl.pydlutils.yanny`_ and
        `pydl.goddard.astro.airtovac`_ instead of internal functions
    | **01 Dec 2016**: (KBW) Relocated from proc to par.
    | **06 Oct 2017**: (KBW) Add function to return channel names


.. include license and copyright
.. include:: ../copy.rst


.. include common links, assuming primary doc root is up one directory
.. include:: ../links.rst
import os
import warnings
import numpy

from pydl.goddard.astro import airtovac
from pydl.pydlutils.yanny import yanny

from .spectralfeaturedb import SpectralFeatureDB
from ..proc.bandpassfilter import BandPassFilterPar

[docs]class AbsorptionIndexDB(SpectralFeatureDB): r""" Basic container class for the database of absorption-line indices. Each row of the database is parsed using :class:`mangadap.proc.bandpassfilter.BandPassFilterPar`. For the format of the input file, see :ref:`spectralindices-absorption`. The primary instantiation requires the SDSS parameter file with the bandpass data. To instantiate using a keyword (and optionally a directory that holds the parameter files), use the :func:`mangadap.par.spectralfeaturedb.SpectralFeatureDB.from_key` class method. See the base class for additional attributes. Args: parfile (:obj:`str`): The SDSS parameter file with the database. Attributes: key (:obj:`str`): Database signifying keyword file (:obj:`str`): File with the data size (:obj:`int`): Number of features in the database. dummy (`numpy.ndarray`_): Boolean array flagging bandpasses as dummy placeholders. """ default_data_dir = 'absorption_indices'
[docs] def _parse_yanny(self): """ Parse the yanny file (provided by :attr:`file`) for the bandhead database. Returns: :obj:`list`: The list of :class:`mangadap.par.parset.ParSet` instances for each line of the database. """ # Read the yanny file par = yanny(filename=self.file, raw=True) if len(par['DAPABI']['index']) == 0: raise ValueError('Could not find DAPABI entries in {0}!'.format(self.file)) # Check if any of the bands are dummy bands and warn the user self.dummy = numpy.any(numpy.array(par['DAPABI']['blueside']) < 0, axis=1) self.dummy |= numpy.any(numpy.array(par['DAPABI']['redside']) < 0, axis=1) self.dummy |= numpy.any(numpy.array(par['DAPABI']['primary']) < 0, axis=1) if numpy.sum(self.dummy) > 0: warnings.warn('Bands with negative wavelengths are used to insert dummy values.' ' Ignoring input bands with indices: {0}'.format( numpy.array(par['DAPABI']['index'])[self.dummy])) # Setup the array of absorption-line index database parameters self.size = len(par['DAPABI']['index']) parlist = [] for i in range(self.size): invac = par['DAPABI']['waveref'][i] == 'vac' comp = par['DAPABI']['component'][i] != 0 parlist += [ BandPassFilterPar(index=par['DAPABI']['index'][i], name=par['DAPABI']['name'][i], blueside=par['DAPABI']['blueside'][i] if invac \ else airtovac(numpy.array(par['DAPABI']['blueside'][i])), redside=par['DAPABI']['redside'][i] if invac \ else airtovac(numpy.array(par['DAPABI']['redside'][i])), primary=par['DAPABI']['primary'][i] if invac \ else airtovac(numpy.array(par['DAPABI']['primary'][i])), units=par['DAPABI']['units'][i], integrand='flambda', component=comp) ] return parlist
[docs] def channel_names(self, offset=0): """ Return a dictionary with the channel names as the dictionary key and the channel number as the dictionary value. An ``offset`` can be added to the channel number; i.e., if the offset is 2, the channel numbers will be a running number starting with 2. """ return {['name'][i] : i + offset for i in range(self.size)}