Multicategory Multilevel 2+ & Sorting Multicategory

[richardnm-2]

update: see #6966 (?)

closes #2175
closes #3723

#2175 requests for a multicategory multilevel (2+). This is great for data visualization on, as mentioned, "Variability Charts".

In order to expand the capabilities of multicategory axis type, the list structure previously implemented has been changed at set_convert.js ax.setupMultiCategory(), adding a new file to src/lib -> sort_traces.js. Working with the traces as a list of objects instead, to try to provide the same data structure to setCategoryIndex() seemed easier. Sorting is performed reversed, in order to achieve a stable sorting. I don't know about the implementation, but the result is the same as if sorted backwards in pandas (Python), or an Excel table.

The capabilities upgrade was then achieved, and the other changes were to make tha axis draw the new data shape, as pushing multiple functions to seq, in a loop, to account for every level. Also, category indexes had to be updated to comply with the new data shape.

The categorical data on the axis was drawn accordingly, but the sorting issue, #3723 showed that this was a known problem. Testing showed that providing the data already sorted to the newPlot function outputed the desired result. So, as the trace levels were already beein looped inside ax.setupMultiCategory(), and the object list was easyly sortable, before transforming it to a matrix again, it made sense to also update gd._fullData with the sorted data. The place to do so may not be the best and some thought can be given to that.

[AndreasUntch]

@richardnm-2 Hello, great to see that someone is working on this and tries to provide a solution :) It is quite a pain with multicategory axis right now. Sorting breaks whenever an item is missing in one stack for example... Hope there will be a fix soon. fyi: We are using plotly in R

[zupdaz]

@richardnm-2 It's fantastic to see your efforts to improve the current handling of multicategory axes. Currently, when a category lacks data points, it can significantly disrupt the visualization integrity. Also, having more than 2 levels is a must for most of modern data analysis. Is this feature still being worked on at the moment?

[PhilippaTreacy]

Is this close to merging? Would be a great feature to have.

[DianYing123]

@richardnm-2 May I inquire about the approach you used to resolve this issue in plotly.py?

[alon-aviv-ni]

Hi, is this PR still in progress? Looking forward for this functionality to be introduced in the library.

[wowoxiapqi]

I really hope this feature will be ok

[lucasrea1998]

What's the status on this PR, looking forward to this being implemented.

[gvwilson]

hi @lucasrea1998 we are currently trying to get a major release out the door and will circle back to re-prioritize backlog once that's done - hopefully mid-November. Thanks - @gvwilson

[dmitrii-erkin]

Hello. Do you have any update regarding this PR, please? Thank you.

[Pfizer-BradleyBare]

I'm super excited to see this almost complete. Will this be merged soon?

[gvwilson]

@Pfizer-BradleyBare unfortunately I don't have a timeline for getting this reviewed and merged :-(