> 0 based is due to programming iteration.

I think it makes sense for enumeration in general to begin at 0. It's a mapping from the natural numbers after all, and zero is the most natural number!

What makes you think of programming iteration as a motivation for zero-based indexing?

Enumeration should generally begin at 1. In common language, you don't say "this person won the 0th place trophy", you say "this person won the 1st place trophy". It's address offsetting that should begin at 0.

C strongly encourages you to think of arrays as simply address+offset pointers, so it absolutely should start with 0.

> you don't say "this person won the 0th place trophy"

I think it would make sense to say it. The reason I don't is that people around me would misunderstand me if I did. (Around some people, it works, though!)

If some told me they got the "0th place trophy", I would take that to be a colorful way of saying they didn't win anything, as 0 means nothing, or the absence of trophies, in this case.

That's just an artefact of being used to a certain way, isn't it? For me, it's about finding fundamental reasons for one convention or another, not about the practicalities.

The reason for not starting at zero for enumeration is that zero means a lack of things to count or list. Therefore, we should start with the one, since that's the first number where we would have reason to enumerate.

Why not say someone won the -1th place trophy? Where does it start?

I start counting at 1 for everything when not programming, so I don't understand this. I always understood zero-based indexing to be primarily a hardware driven concern, with C being fairly close to assembly, and so many languages ended up copying C's syntax.

> To quote wikipedia on Zero-based "Zero-based numbering or index origin = 0[1][2] is a way of numbering in which the initial element of a sequence is assigned the index 0, rather than the index 1 as is typical in everyday non-mathematical/non-programming circumstances."

1 Based

0 = 1

1 = 2

Zero based

0 = nothing

1 = 1

Seem important for mathematics.

Also head and tail in Pandas is 1 based! That drove me crazy.

print(users[users.age > 25].head(3))

Returns 3 elements and not 4!

Is it possible that the argument to `head` is the _number_ of elements to return, and that the choice of indexing therefore doesn't enter the picture?

Actually, even if the argument (3 in this case) were an index, I would expect it to be the index of the first element _not_ to fetch, like how intervals typically are written with an inclusive lower bound and an exclusive upper bound as in "2 ≤ i < 13" [0]. That would make the result you're getting consistent with zero-indexing, but not with one-indexing.

Of course, I don't know what Pandas is like outside this particular example, or what Pandas even is. A database thing?

[0] https://www.cs.utexas.edu/users/EWD/ewd08xx/EWD831.PDF