MolecularAtmosphere.ussa_1976() fix

[nollety]

Description

Hotfix for an issue described in #332, that affects MolecularAtmosphere.ussa_1976().
This fix is not intended to remain very long; I expect the next atmosphere design (due for end of the month) to include a default (ckd/mono) absorption dataset that supports most spectral settings so that the default atmosphere constructor can be used across many (spectral and thermophysical) settings.

Changes

I have added a wavelength_range optional (defaults to 545-555 nm) parameter to the MolecularAtmosphere.ussa_1976 constructor that provide the information required for the constructor to automatically open the relevant absorption datasets. This makes the default constructor usable again:

atmosphere = MolecularAtmosphere.ussa_1976()

New usage

• To instantiate a USSA 1976 molecular atmosphere:

  atmosphere = MolecularAtmosphere.ussa_1976()

  This atmosphere can be integrated in any experiment targetting wavelengths within [545, 555] nm

• Outside of [545, 555] nm, specify the desired wavelength range, e.g.:

  from eradiate import unit_registry as ureg
  
  atmosphere = MolecularAtmosphere.ussa_1976(
    wavelength_range=[1580, 1630] * ureg.nm,
  )

Notes

Follow-up/related to: Experiments context used for initialization

Checklist

• The code follows the relevant coding guidelines
• The code generates no new warnings
• The code is appropriately documented
• The code is tested to prove its function
• The feature branch is rebased on the current state of the main branch
• I updated the change log if relevant
• I give permission that the Eradiate project may redistribute my contributions under the terms of its license

[leroyvn]

Hi @nollety, thanks for taking care of this. I made a few specific comments; in addition, I have a couple of general comments / questions:

• Please briefly document the new syntax in this PR. It is referenced by the change log and will help users upgrade their codebase if they need.
• Depending on the number of files, is it much more harmlful to xr.open_mfdataset() all the files? Doing so would considerably simplify the logic.

[nollety]

• Depending on the number of files, is it much more harmlful to xr.open_mfdataset() all the files? Doing so would considerably simplify the logic.

xr.open_mfdataset() takes a string glob or a list of files to open as first parameter. That does not work here because we have a list of datasets (they are opened so that they can be sliced along the wavelength dimension).

This is also planned for an upgrade with thermoprops-next (support for customized atmospheric profiles).

[leroyvn]

Hi @nollety, I have a few more comments.

[nollety]

All tests passed except
tests/01_eradiate/02_system/test_basic.py::test_radiometric_accuracy[mono_single-1.0-constant-500000.0] which failed by a few decimals (see test output exerpt below).

E           AssertionError: 
E           Not equal to tolerance rtol=0.001, atol=0
E           
E           Mismatched elements: 1 / 10 (10%)
E           Max absolute difference: 0.00054938
E           Max relative difference: 0.00109875
E            x: array([0.499653, 0.500549, 0.500051, 0.499704, 0.500148, 0.499981,
E                  0.50008 , 0.499871, 0.499665, 0.49982 ], dtype=float32)
E            y: array([0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5])

[leroyvn]

All tests passed except tests/01_eradiate/02_system/test_basic.py::test_radiometric_accuracy[mono_single-1.0-constant-500000.0] which failed by a few decimals (see test output exerpt below).

E           AssertionError: 
E           Not equal to tolerance rtol=0.001, atol=0
E           
E           Mismatched elements: 1 / 10 (10%)
E           Max absolute difference: 0.00054938
E           Max relative difference: 0.00109875
E            x: array([0.499653, 0.500549, 0.500051, 0.499704, 0.500148, 0.499981,
E                  0.50008 , 0.499871, 0.499665, 0.49982 ], dtype=float32)
E            y: array([0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5, 0.5])

This is unrelated with this PR. The test using the new illumination model barely passes the threshold and fails on several of my machines, but not always. I'll try and fix that now.

[leroyvn]

Thanks @nollety, looks like we're good to go 🚀