def get_raw_tables(query):
"""(Down)load LAMDA data as astropy tables."""
# lazy import of astropy-related things
from astroquery.lamda import Lamda
from astroquery.lamda import parse_lamda_datafile
# case 1: try to get by URL
if query.startswith("http"):
name = Path(urlparse(query).path).stem
Lamda.molecule_dict[name] = query
return Lamda.query(name)
# case 2: try to get by local path
path = Path(query).expanduser().resolve()
if path.exists():
return parse_lamda_datafile(path)
# case 3: try to get by astroquery
try:
return Lamda.query(Path(query).stem)
except Exception:
raise ValueError(query)
def test_einstein():
transition_freq_list = [(1611.7935180 * u.GHz).to('MHz'),
(177.26111120 * u.GHz).to('MHz')]
mol_tag_list = [28001, 27001]
temp_estimate = 300. * u.K
result = []
catalog_result = []
cat = JPLSpec.get_species_table()
for i in range(2):
transition_freq = transition_freq_list[i]
mol_tag = mol_tag_list[i]
mol_data = Phys.from_jplspec(temp_estimate, transition_freq, mol_tag)
intl = intensity_conversion(mol_data)
mol_data.apply([intl.value] * intl.unit, name='intl')
au = einstein_coeff(mol_data)
result.append(au.value)
mol = cat[cat['TAG'] == mol_tag]
mol_name = mol['NAME'].data[0]
lam_search = Lamda.query(mol=mol_name.lower())
lam_result = lam_search[1]
tran = transition_freq.to('GHz').value
lam_found = lam_result[lam_result['Frequency'] == tran]
au_cat = lam_found['EinsteinA']
au_cat = au_cat.data[0]
catalog_result.append(au_cat)
err = (abs((np.array(catalog_result) - np.array(result)) /
np.array(catalog_result) * 100))
assert np.all(err < 23.5)
def get_datafile(species, savedir='./'):
"""
Load a molecular data file and save it into the specified directory
"""
from astroquery.lamda import Lamda
datapath = os.path.join(savedir,species)
species,suffix = os.path.splitext(species)
if suffix == "":
datapath += ".dat"
elif suffix != ".dat":
raise ValueError("Molecular data file must either be a species name or species.dat")
if not os.path.isdir(savedir):
mkdir_p(savedir)
if not os.path.isfile(datapath):
data = Lamda.query(species, return_datafile=True)
with open(datapath,'w') as out:
out.writelines([d+"\n" for d in data])
return os.path.split(datapath)
import pylab as pl
from astropy import units as u
from astroquery.lamda import Lamda, utils as lamutils
from astropy.utils.console import ProgressBar
ech3oh = Lamda.query('e-ch3oh')
lamutils.ncrit(ech3oh, 256, 253, 100)
crates, transitions, levels = ech3oh
upperenergy = [
transitions['E_u(K)'][transitions['Upper'] == upper][0]
for upper in crates['H2']['Upper']
]
ncrits = [
lamutils.ncrit(ech3oh, upper, lower, 100) for upper, lower in ProgressBar(
list(zip(transitions['Upper'], transitions['Lower'])))
]
Jvals = {
level: int(levels[levels['Level'] == level]['J'][0].split("_")[0])
for level in levels['Level']
}
pl.figure(4).clf()
pl.semilogy(upperenergy, crates['H2']['C_ij(T=200)'], '.')
pl.xlabel("$E_U$ (K)")
pl.ylabel("$C_{ij}$ at $T=200$ K")
pl.figure(1).clf()
pl.semilogy(transitions['Upper'], u.Quantity(ncrits), '.')
import pylab as pl
from astropy import units as u
from astroquery.lamda import Lamda, utils as lamutils
from astropy.utils.console import ProgressBar
ech3oh = Lamda.query("e-ch3oh")
lamutils.ncrit(ech3oh, 256, 253, 100)
crates, transitions, levels = ech3oh
upperenergy = [transitions["E_u(K)"][transitions["Upper"] == upper][0] for upper in crates["H2"]["Upper"]]
ncrits = [
lamutils.ncrit(ech3oh, upper, lower, 100)
for upper, lower in ProgressBar(list(zip(transitions["Upper"], transitions["Lower"])))
]
Jvals = {level: int(levels[levels["Level"] == level]["J"][0].split("_")[0]) for level in levels["Level"]}
pl.figure(4).clf()
pl.semilogy(upperenergy, crates["H2"]["C_ij(T=200)"], ".")
pl.xlabel("$E_U$ (K)")
pl.ylabel("$C_{ij}$ at $T=200$ K")
pl.figure(1).clf()
pl.semilogy(transitions["Upper"], u.Quantity(ncrits), ".")
pl.xlabel("Level ID")
pl.ylabel("$n_{crit}$ [cm$^{-3}$]")
pl.figure(3).clf()
pl.semilogy([Jvals[lid] for lid in transitions["Upper"]], u.Quantity(ncrits), ".")
