Add the ipynb from ECR topotoolbox webinar of June 2026

[bgailleton]

The notebook presented at the workshop + the addition of a README.md to briefly guide through the examples

[wkearn]

A few things:

Could you give the notebook a slightly more descriptive title? We end up with two notebooks called "Graphflood in pytopotoolbox" and "GraphFlood: a large-scale hydrodynamics module for TopoToolbox," and it is hard to know what the difference is between the two. You could mention the webinar or be more specific about what is in there. If you want to change the title of the other one, you could do that too.

Usually, we have the "Author," "Highlighted References," and "Audience" sections at the beginning, just to help orient people and be somewhat consistent. Up to you, though.

Something about the custom formatting also seems to interfere with the layout of sphinx/nbsphinx:

I haven't been able to figure out exactly what's going on here. sphinx produces some warnings:

/home/wkearn/files/projects/topotoolbox/code/gallery/work/notebooks/python/graphflood/Workshop_06_2026.ipynb:120: WARNING: Title underline too short.

🌊 Graphflood in ``pytopotoolbox``
=================================
/home/wkearn/files/projects/topotoolbox/code/gallery/work/notebooks/python/graphflood/Workshop_06_2026.ipynb:293: WARNING: Title underline too short.

📦 Prerequisites
~~~~~~~~~~~~~~~
/home/wkearn/files/projects/topotoolbox/code/gallery/work/notebooks/python/graphflood/Workshop_06_2026.ipynb:611: WARNING: Title underline too short.

⚡ Quickstart
============
/home/wkearn/files/projects/topotoolbox/code/gallery/work/notebooks/python/graphflood/Workshop_06_2026.ipynb:611: WARNING: Title underline too short.

⚡ Quickstart
============
/home/wkearn/files/projects/topotoolbox/code/gallery/work/notebooks/python/graphflood/Workshop_06_2026.ipynb:662: CRITICAL: Title level inconsistent:
...

but I don't know if that is related.

You should be able to install the necessary packages from the gallery requirements.txt file and run make html to test locally.

I would probably remove most of the custom html/css just for simplicity, but if you can figure out a way to get everything properly visible on the gallery with some more style, I'm all for it.

[bgailleton]

I'll probably refine the titles on both notebooks and append the missing sections.

I love my HTML injections and that's my thing for notebook currently, but I did not realise it would probably mess the website integration - I am 99% sure this is causing the obscure errors and that it's not reccomended for web display in general. I can live without them, they were mostly important for the live coding with the screen sharing where it can be difficult to read a regular notebook.

I'll try to do that whi week

[bgailleton]

(I am on the field until the end of next week but it's still on my todo list)