[emacs-berlin] July 2025 Meetup is next week

[jman]

Hello everyone!

Nice meeting yesterday, the Task Juggler show-and-tell was cool (see other email from Sebastian).
Also interesting the discussion about GNU Hyperbole, a package from outer space :)

I have asked a seemingly "simple" question about how to calculate aggregates in an orgmode table by 
date ranges. For example: how to calculate the total KM for July?

--8<---------------cut here---------------start------------->8---
| Date             |    KM | TOT Monat |
|------------------+-------+-----------|
| [2025-07-16 Wed] |  28.6 |           |
| [2025-07-17 Thu] |     6 |           |
| [2025-07-18 Fri] |    12 |           |
| [2025-07-19 Sat] |    18 |           |
| [2025-07-20 Sun] |    18 |           |
| [2025-07-21 Mon] |    10 |           |
| [2025-07-22 Tue] |    14 |           |
| [2025-07-23 Wed] |     9 |           |
| [2025-07-28 Mon] |    12 |           |
| [2025-07-29 Tue] |    12 |           |
| [2026-07-29 Wed] |    14 |           |
|------------------+-------+-----------|
| Total            | 153.6 |           |
#+TBLFM: @>$2=vsum(@2.. at -1)
--8<---------------cut here---------------end--------------->8---

We investigated using the package https://github.com/tbanel/orgaggregate which seems to be *almost* 
what I need but yet it doesn't seem to handle date ranges nicely. As suggested during the 
discussion, probably the other meaningful way is writing down some elisp code in a formula. Any 
suggestion for practical, alternative approaches are welcome.

As a reminder, in person meetups are held in closed spaces. It is therefore appreciated if attendees 
with symptoms of cold or sickness could kindly consider attending online.

See you next time!

Best,