Additional aggregation functions: range and change

[bhogan-mitre]

I would like to use some additional, fairly simple, functions for aggregations. Per brief exchange on the community site, it seems like Plotly would be open to including more functions.

Two functions I would suggest are:

• range: max - min
• change: last - first

[alexcjohnson]

Sure, those both sound completely reasonable. Would you like to make a PR to add them? In addition to adding them as attribute values as you already mentioned in the community post, they just need to be added in getAggregateFunction and then included briefly in the aggregation test suite

[bhogan-mitre]

Yes, I will try to put together a PR for this. Thanks for links to the other touch points for these functions!

[bhogan-mitre]

PR into my own fork is linked above. Please let me know if you have any suggestions on this, @alexcjohnson. Thanks in advance.

[bhogan-mitre]

Thanks for the review! Linked above is a PR into the main repo.