import numpy as np
from astropy import units as u
import pandas as pd
[docs]def read_artis_density(fname):
"""
Reading a density file of the following structure (example; lines starting with a hash will be ignored):
The first density describes the mean density in the center of the model and is not used.
5
#index velocity [km/s] log10(density) [log10(g/cm^3)]
0 1.1e4 1.6e8
1 1.2e4 1.7e8
Parameters
----------
fname : str
filename or path with filename
Returns
-------
time_of_model : astropy.units.Quantity
time at which the model is valid
data : pandas.DataFrame
data frame containing index, velocity (in km/s) and density
"""
with open(fname) as fh:
for i, line in enumerate(open(fname)):
if i == 0:
no_of_shells = np.int64(line.strip())
elif i == 1:
time_of_model = u.Quantity(float(line.strip()), "day").to("s")
elif i == 2:
break
artis_model_columns = [
"index",
"velocities",
"mean_densities_0",
"ni56_fraction",
"co56_fraction",
"fe52_fraction",
"cr48_fraction",
]
artis_model = pd.read_csv(
fname,
skiprows=2,
usecols=(0, 1, 2, 4, 5, 6, 7),
dtype={item: np.float64 for item in artis_model_columns},
names=artis_model_columns,
# The argument `delim_whitespace` was changed to `sep`
# because the first one is deprecated since version 2.2.0.
# The regular expression means: the separation is one or
# more spaces together (simple space, tabs, new lines).
sep=r"\s+",
).to_records(index=False)
velocity = u.Quantity(artis_model["velocities"], "km/s").to("cm/s")
mean_density = u.Quantity(10 ** artis_model["mean_densities_0"], "g/cm^3")[
1:
]
return time_of_model, velocity, mean_density