Update dashboard for new date format in database

[RemiLehe]

The database has an entry "date" for each data point. Data used to be stored in the form of a string (e.g. "2025-03-20 13:00:02"). However, in pymongo, it is more standard and efficient to store the date as a datetime object.

I recently updated the database to ensure that this is now the case.

Accordingly, the code in the dashboard that loads the database now needs to convert this datetime object to a string. (This string is displayed, for the experimental points, when hovering on a point.)

[RemiLehe]

This solves a previously existing issue, where the hover box would show date=NaN, because the code attempted to format a string (e.g. 2026-01-16 12:00:00) with .4g which is for numerical values (displaying them with 4 significant digits).

[EZoni]

I think this could be done with less code. Would this work?

Suggested change

	# Check if column is "date"
	if col == "date":
	# For string/date columns, use no format specifier (displays as-is)
	section.append(
	f"{col}=%{{customdata[{hover_data.index(col)}]}}"
	)
	else:
	# Use numeric formatting for numeric columns
	section.append(
	f"{col}=%{{customdata[{hover_data.index(col)}]:.4g}}"
	)
	# For string/date columns, use no format specifier (displays as-is)
	format = "" if col == "date" else ".4g"
	section.append(
	f"{col}=%{{customdata[{hover_data.index(col)}]{format}}}"
	)

This simpler example works for me, not sure if the %{} syntax above breaks it:

format = "" if col == "date" else ".4g"
value = 1.23456789
string = f"{value:{format}}"

It prints '1.23456789' if you set col = "date" and '1.235' otherwise.

[EZoni]

I think this could be done with less code. Would this be equivalent?

# Store '_id', 'date' as string
for key in ["_id", "date"]:
    if key in exp_data.columns:
        exp_data[key] = exp_data[key].astype(str)
    if key in sim_data.columns:
        sim_data[key] = sim_data[key].astype(str)