AxsDB — The Eradiate Absorption Cross-section Database Interface

This library provides an interface to read and query the absorption databases of the Eradiate radiative transfer model.

Features

• Monochromatic and CKD databases: Read and evaluate absorption coefficients for both monochromatic and correlated-k distribution spectral representations.
• Fast interpolation: Numba-accelerated multi-dimensional interpolation of thermophysical profiles (pressure, temperature, mole fractions).
• Configurable error handling: Fine-grained, per-coordinate control over out-of-bounds behaviour (clamp, fill, raise, warn).
• Efficient I/O: Lazy or eager loading of NetCDF data files, with LRU caching for repeated lookups.
• xarray and Pint integration: Works natively with xarray datasets and Pint quantities.
• CLI: Validate database integrity from the command line with axsdb check.

Installation

Python 3.9 or later is required.

pip install axsdb

Quick start

import xarray as xr
from axsdb import MonoAbsorptionDatabase
from axsdb.units import get_unit_registry

ureg = get_unit_registry()

# Open a database directory
db = MonoAbsorptionDatabase.from_directory("path/to/database")

# Load a thermophysical profile
thermoprops = xr.load_dataset("path/to/thermoprops.nc")

# Evaluate the absorption coefficient at a given wavelength
sigma_a = db.eval_sigma_a_mono(
    w=550.0 * ureg.nm,
    thermoprops=thermoprops,
)

For CKD databases, use CKDAbsorptionDatabase and eval_sigma_a_ckd (which takes an additional g parameter for the quadrature point).

CLI

AxsDB ships a command-line tool to validate databases:

# Check a monochromatic database
axsdb check path/to/database -m mono

# Check and fix missing index files
axsdb check path/to/database -m ckd --fix

Documentation

Full documentation is available at axsdb.readthedocs.io.

License

AxsDB is distributed under the terms of the GNU Lesser General Public License v3.0.