Source code for astroquery.exoplanet_orbit_database.exoplanet_orbit_database

# Licensed under a 3-clause BSD style license - see LICENSE.rst
from __future__ import (absolute_import, division, print_function,
                        unicode_literals)
import json
import os

from astropy.utils.data import download_file
from astropy.io import ascii
from astropy.table import QTable
import astropy.units as u
from astropy.coordinates import SkyCoord

__all__ = ['ExoplanetOrbitDatabase']

EXOPLANETS_CSV_URL = 'http://exoplanets.org/csv-files/exoplanets.csv'
TIME_ATTRS = {'TT': 'jd', 'T0': 'jd'}
BOOL_ATTRS = ('ASTROMETRY', 'BINARY', 'EOD', 'KDE', 'MICROLENSING', 'MULT',
              'SE', 'TIMING', 'TRANSIT', 'TREND')


[docs]class ExoplanetOrbitDatabaseClass(object): """ Exoplanet Orbit Database querying object. Use the ``get_table`` or ``query_planet`` methods to get information about exoplanets via the Exoplanet Orbit Database. """ def __init__(self): self._param_units = None self._table = None @property def param_units(self): if self._param_units is None: module_dir = os.path.dirname(os.path.abspath(__file__)) units_file = open(os.path.join(module_dir, 'data', 'exoplanet_orbit_database_units.json')) self._param_units = json.load(units_file) return self._param_units
[docs] def get_table(self, cache=True, show_progress=True, table_path=None): """ Download (and optionally cache) the `Exoplanet Orbit Database planets table <http://www.exoplanets.org>`_. Parameters ---------- cache : bool (optional) Cache exoplanet table to local astropy cache? Default is `True`. show_progress : bool (optional) Show progress of exoplanet table download (if no cached copy is available). Default is `True`. table_path : str (optional) Path to a local table file. Default `None` will trigger a download of the table from the internet. Returns ------- table : `~astropy.table.QTable` Table of exoplanet properties. """ if self._table is None: if table_path is None: table_path = download_file(EXOPLANETS_CSV_URL, cache=cache, show_progress=show_progress) exoplanets_table = ascii.read(table_path) # Store column of lowercase names for indexing: lowercase_names = [i.lower().replace(" ", "") for i in exoplanets_table['NAME'].data] exoplanets_table['NAME_LOWERCASE'] = lowercase_names exoplanets_table.add_index('NAME_LOWERCASE') # Create sky coordinate mixin column exoplanets_table['sky_coord'] = SkyCoord(ra=exoplanets_table['RA'] * u.hourangle, dec=exoplanets_table['DEC'] * u.deg) # Assign units to columns where possible for col in exoplanets_table.colnames: if col in self.param_units: # Check that unit is implemented in this version of astropy if hasattr(u, self.param_units[col]): exoplanets_table[col].unit = u.Unit(self.param_units[col]) self._table = QTable(exoplanets_table) return self._table
[docs] def query_planet(self, planet_name, table_path=None): """ Get table of exoplanet properties. Parameters ---------- planet_name : str Name of planet table_path : str (optional) Path to a local table file. Default `None` will trigger a download of the table from the internet. Returns ------- table : `~astropy.table.QTable` Table of one exoplanet's properties. """ exoplanet_table = self.get_table(table_path=table_path) return exoplanet_table.loc[planet_name.strip().lower().replace(' ', '')]
ExoplanetOrbitDatabase = ExoplanetOrbitDatabaseClass()