Enhancement: add "sum" to pandas.describe()

[darindillon]

Feature request: can we add "sum" to the pandas.describe() method? Not every dataset cares about sum, of course, but enough datasets do care about it that it seems worth adding to the default describe() method. (For instance, financial applications where you have multiple columns representing different scenarios, and you want to see how much profit would be earned of each scenario).

[jreback]

xref #7014

I am a bit - on this ATM as .aggregate/.agg will be easily able to do this pretty generically.

[jorisvandenbossche]

I also leaning to "not needed to add it" (you already have many statistics, adding one more makes the output more complex).

(for reference, R's summary also does not include sum, not that we cannot deviate from that of course)

[darindillon]

Well yes, you can always call .describe() to get some of the statistics and also call .agg() to get other statistics and alsocall something else to get other statistics and then merge them all together; but of course that's more work. Obviously, .describe() can't contain everything, it should contains the "commonly used" ones; and what's "commonly used" for you may be different than for me.
But I would argue that (especially for financial applications) "sum" is a very common metric it's worth including. (If this were an exotic metric like "kurtosis" that most people don't understand, we wouldn't include it; but "sum" is useful to lots of people).

If I did all the work to add this (including test cases, etc) and submitted a PR, would you be willing to consider including it?

[jorisvandenbossche]

It is difficult to assess, as I am also biased by the type of data I am working with, but I think sum is less generally applicable as the others.
For example, I work with time series data of concentrations. For such a case, all current statistics are useful (or at least mean something), while a sum makes no sense. And I have the feeling that this can be generalized, meaning that the current (distribution) statistics almost always make some sense, while for sum it much more depends on the type of data.

[TomAugspurger]

I'm also -0 on this. I think focusing on DataFrame.agg would be more useful than modifying describe.