RADIS is a fast line-by-line code for high resolution infrared molecular spectra (emission / absorption, equilibrium / nonequilibrium).
Includes post-processing tools to compare experimental spectra and spectra calculated with RADIS or other spectral codes.
User guide, install procedure and examples are available on the RADIS Website:
Assuming you have Python installed with the Anaconda distribution just use:
pip install radis
That's it! You can now run your first example below. If you encounter any issue, or to upgrade the package later, please refer to the detailed installation procedure .
from radis import calc_spectrum s = calc_spectrum(1900, 2300, # cm-1 molecule='CO', isotope='1,2,3', pressure=1.01325, # bar Tgas=700, # K mole_fraction=0.1, path_length=1, # cm ) s.apply_slit(0.5, 'nm') # simulate an experimental slit s.plot('radiance')
Calculate a CO nonequilibrium spectrum from the HITRAN database (on your first call, this will calculate and cache the CO(X) rovibrational energies):
s2 = calc_spectrum(1900, 2300, # cm-1 molecule='CO', isotope='1,2,3', pressure=1.01325, # bar Tvib=700, # K Trot=300, # K mole_fraction=0.1, path_length=1, # cm ) s2.apply_slit(0.5, 'nm') s2.plot('radiance', nfig='same') # compare with previous
The Quick Start examples automatically download the line databases from HITRAN-2016, which is valid for temperatures below 700 K.
For high temperature cases, you may need to use other line databases such as
HITEMP-2010 (typically T < 2000 K) or CDSD-4000 (T < 5000 K). These databases must be described in a
from numpy import loadtxt from radis import experimental_spectrum, plot_diff w, I = loadtxt('my_file.txt').T # assuming 2 columns sexp = experimental_spectrum(w, I, Iunit='mW/cm2/sr/nm') plot_diff(sexp, s) # comparing with spectrum 's' calculated previously
Typical output of plot_diff:
In the browser (no installation needed!)
Alternatively, you can also run RADIS directly in the browser with the RADIS Interactive Examples project. For instance, run the Quick Start example on the link below:
Or start a bare RADIS online session:
For reproducibility, do not forget to cite the line database used, and the spectroscopic constants if running nonquilibrium calculations. See How to cite?
RADIS internals are described in the Developer Guide
The code is available on this repository under GNU LESSER GENERAL PUBLIC LICENSE (v3)
If encountering any problem, first refer to the list of known Issues on GitHub. We appreciate your feedback and suggestions!
For any question, please join the discussion channel on Gitter: or the Q&A Forum
- Help: Q&A forum
- Source Code:
- Test Status:
- PyPi Repository:
- Interactive Examples: radis_examples
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