Closes #<2841> documentation derive vars dt clarify highest imputation definitions expand min dates example and add max dates example

[LaurentDassencourt]

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Definition of Done from the issue:

• [x] Functions argument where letters are specified, e.g. "Y" and "n" have the meanings of the letters explained next to them, i.e. If "n" (none, lowest level) is specified...
• [x] The min_dates example has text corrected (see below comment) and is expanded to be more records/scenarios.
• [x] A max_dates example is created that has similar records/scenarios.

[github-actions[bot]]

Package	Line Rate	Health
admiral	100%	✔
Summary	100% (5714 / 5722)	✔

[LaurentDassencourt]

Just for a sanity check - can you review the max and min date arguments in the tests and make sure we have some deeper coverage - the arguemnts are covered but we tend to not go very deep? Maybe even these examples could be just thrown in as the tests?

It seems to me that the existing tests cover the handling of minimum and maximum dates. The new examples do not seem to add much to the tests. If i'm wrong or If you have a specific case in mind to test, please let me know.

[bms63]

Just for a sanity check - can you review the max and min date arguments in the tests and make sure we have some deeper coverage - the arguemnts are covered but we tend to not go very deep? Maybe even these examples could be just thrown in as the tests?

It seems to me that the existing tests cover the handling of minimum and maximum dates. The new examples do not seem to add much to the tests. If i'm wrong or If you have a specific case in mind to test, please let me know.

Thanks for check!! No need to add more tests if looking sufficient.