Example 2 for Butterfly chart (version2)

[SimaRaha]

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[SimaRaha]

Hi Greg and Liam,

I've converted this pull request to a draft as we're still working on finalizing some aspects. I'll let you know once it's ready for review.

[rl-utility-man]

This is a continuation of #4994
I rebased the git commit to make this readable and erased the history, but @SimaRaha built a complete example and had the key insight about using a secondary x axis with a separate domain.

[gvwilson]

@LiamConnors can you please review for the Plotly.py 6.1 release?

[LiamConnors]

Is there a reason to rename the column here rather in the dataset? Is that just how the dataset was?

[rl-utility-man]

It's a shortcoming of the data set. I just proposed a PR to label the column properly in the data set plotly/datasets#64 A search of github shows no uses of that data set other than in this PR and #4994, so it appears safe to accept that PR. (I uploaded this data set recently in plotly/datasets#62 )

[LiamConnors]

Would it be possible to put more of the layout and data in the go.Figure object. I think update_layout and other can be a bit more challenging to understand for a user.

[LiamConnors]

Suggested change

	Diverging bar charts offer two imperfect options for responses that are neither positive nor negative: put them in a separate column, as in this example or omit them as in the example above. That leaves the unreported neutral value implicit when the categories add to 100%, Jonathan Schwabish discusses this on page 92-97 of _Better Data Visualizations_.
	The previous diverging bar chart example excluded neutral responses. Another option, as shown in this example, is to include them in a separate column.

I think the content around "unreported neutral values" refers the previous example? If so, I think that would be more relevant there. Also, from documentation, I'd prefer not to direct users to additional resources that they may not have access to.

[LiamConnors]

The example doesn't run for me, and I believe it's related to setting of the xaxis here.