The line with the mesh grid makes an array that is x by y. ... That way, the next time I do a search for "3d plot in plotly" I will find this post and the comments will be useful to me ...

Plotly Unveils AI-Native Plotly Studio™ and Plotly Cloud™, Bringing Vibe-Coding to Visual Data App Development Plotly Technologies Mon, Jun 2, 2025, 9:00 AM 3 min read ...