"""
Module with reading functionalities for data from individual objects.
"""
import os
import math
import configparser
import h5py
import numpy as np
from species.util import phot_util
[docs]class ReadObject:
"""
Class for reading data from an individual object from the database.
"""
def __init__(self,
object_name):
"""
Parameters
----------
object_name : str
Object name as stored in the database (e.g. 'beta Pic b', 'PZ Tel B').
Returns
-------
NoneType
None
"""
self.object_name = object_name
config_file = os.path.join(os.getcwd(), 'species_config.ini')
config = configparser.ConfigParser()
config.read_file(open(config_file))
self.database = config['species']['database']
with h5py.File(self.database, 'r') as h5_file:
if 'objects/'+self.object_name not in h5_file:
raise ValueError(f'The object \'{self.object_name}\' is not present in the '
f'database.')
[docs] def get_photometry(self,
filter_name):
"""
Function for extracting the photometry of the object.
Parameters
----------
filter_name : str
Filter ID.
Returns
-------
numpy.ndarray
Apparent magnitude (mag), magnitude error (error), flux (W m-2 micron-1),
flux error (W m-2 micron-1).
"""
with h5py.File(self.database, 'r') as h5_file:
obj_phot = np.asarray(h5_file['objects/'+self.object_name+'/'+filter_name])
return obj_phot
[docs] def get_spectrum(self):
"""
Function for extracting the spectrum of the object.
Returns
-------
numpy.ndarray
Wavelength (micron), flux (W m-2 micron-1), and flux error (W m-2 micron-1).
"""
with h5py.File(self.database, 'r') as h5_file:
spectrum = np.asarray(h5_file['objects/'+self.object_name+'/spectrum'])
return spectrum
[docs] def get_instrument(self):
"""
Function for extracting the instrument name of the spectrum.
Returns
-------
str
Instrument that was used for the spectrum.
"""
with h5py.File(self.database, 'r') as h5_file:
if 'objects/'+self.object_name+'/spectrum' in h5_file:
dset = h5_file['objects/'+self.object_name+'/spectrum']
instrument = dset.attrs['instrument']
else:
instrument = None
return instrument
[docs] def get_distance(self):
"""
Function for extracting the distance to the object.
Returns
-------
float
Distance (pc).
"""
with h5py.File(self.database, 'r') as h5_file:
obj_distance = np.asarray(h5_file['objects/'+self.object_name+'/distance'])[0]
return float(obj_distance)
[docs] def get_absmag(self,
filter_name):
"""
Function for calculating the absolute magnitudes of the object from the apparent
magnitudes and distance. The errors on the apparent magnitude and distance are propagated
into an error on the absolute magnitude.
Parameters
----------
filter_name : str
Filter ID.
Returns
-------
float, float
Absolute magnitude (mag), uncertainty (mag).
"""
with h5py.File(self.database, 'r') as h5_file:
obj_distance = np.asarray(h5_file['objects/'+self.object_name+'/distance'])
obj_phot = np.asarray(h5_file['objects/'+self.object_name+'/'+filter_name])
abs_mag = phot_util.apparent_to_absolute(obj_phot[0], obj_distance[0])
dist_err = obj_distance[1] * (5./(obj_distance[0]*math.log(10.)))
abs_err = math.sqrt(obj_phot[1]**2 + dist_err**2)
return abs_mag, abs_err