Sylwester Arabas

thank you @tluettm !

CC: @emmacware The convergence exercise is solved here: https://github.com/slayoo/MoAC/blob/master/notebooks/03_MPDATA_error_analysis.ipynb

CI reports this failure (https://github.com/open-atmos/PyMPDATA/actions/runs/15725758755/job/44315180539?pr=578): ``` File "/home/runner/work/PyMPDATA/PyMPDATA/./PyMPDATA/options.py", line 37, in Options dtype: np.float32 | np.float64 = np.float64, TypeError: unsupported operand type(s) for |: 'type' and 'type' ```

closing as it is now part of #1687

@emmacware, reopened this PR to separate the alpha-sampling changes from the Hill & Shipway PR (#1687). Thus, removed any changes to the H&S example from this PR. The remaining notebook...

@emmacware, please push here the fix removing the "wiggle" - let's try to merge it! Thanks

thank you @emmacware !

CI reports this failure (https://github.com/open-atmos/PyMPDATA/actions/runs/15552679887/job/43825446170?pr=576): ``` File "/home/runner/work/PyMPDATA/PyMPDATA/examples/PyMPDATA_examples/comparison_against_pypde_2025/diffusion_2d.py", line 69 type Two2DiffusionSolution = npt.NDArray[np.float64] ^ SyntaxError: invalid syntax ```

>  I have a problem with dependencies. If python's version is 3.11 or lower, the requries numba's version is lower than 0.59 required by py-pde. Because of that, the...

> > could we work with an older version of py-pde on CI? > > I tried downgrading py-pde, but the earliest version that doesn't have the numba requirement is...