docs: Fr/sequential example

[rodriguesfred]

Description

Some examples of sequential data

Summary

Some examples of sequential data

Changes Made

• Example of map using discrete sequential scale as per the Analysis function website.
• Example using heatmaps. Had to find a gov dataset may not be the best example.

Related Issues

• Fixes #
• Closes Add sequential palette example (Plotly) #154

[Copilot]

Pull request overview

This PR adds sequential colour palette usage examples to the Plotly cookbook, addressing issue #154. It introduces two new chart types: a choropleth map of England showing visual impairment certification rates (using geopandas and a government open data API), and a heatmap of domestic energy price indices (using a local .xlsx file).

Changes:

• New choropleth map section using the sequential palette with discrete quintile categories and a custom legend
• New heatmap section using the sequential palette applied as a continuous colorscale

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[nickhenden]

Copilot did a pretty good job! I think I agree with all of it's comments.

Could you address these comments @rodriguesfred then I'll take a second look.

[rodriguesfred]

ready to review again @nickhenden

[nickhenden]

I've not had time to review the code but I spotted some issues when trying to run it.

[nickhenden]

Sorry for the massive delay in reviewing. The charts look great :)

A lot of my suggestions are about reducing code. I appreciate there's a lot of steps needed to reproduce the map, but I don't want to put people off with tons of code if it's not necessary for demonstrating the package and/or common techniques.

[rodriguesfred]

@nickhenden I think I addressed all the comments (maybe) got hard to track LOL

[nickhenden]

Thanks Fred, looks like you've resolved everything :) Three minor tweaks then I think we're good to go

[nickhenden]

Thanks! Approved :)