4 ms·

This is very much a non-argument. Call the columns the 4th and 7th is as arbitrary as calling them the 3rd and the 6th. Again, 0-based indexing exists to fit a

• coldtea 8y ago
  >Call the columns the 4th and 7th is as arbitrary as calling them the 3rd and the 6th. No, that's their ordinal position, and how 8 billion non-programmers would refer them as in any everyday setting. That's also how programmers would refer to them if it wasn't for a historical accident. What's more, that's also how programmers refer to them when they talk between then and not to the machine ("check the 3rd column" not "check the column at the index of 2").
• e12e 8y ago
  a = b[1..n]?
• DNF2 8y ago
  The equivalent of `a = b[:n]` is `a = b[1:n]`. And I don't think you can get around admitting that there is a fundamental ambiguity in the spoken statement "Take a look at the fourth column!" in a zero-based index system. You always need a follow-up question to clarify whether you mean "everyday informal speech fourth" or "zero-index fourth."
  • beojan 8y ago
    But you can say "Take a look at column 4" instead, which is unambiguous.
• Certhas 8y ago
  It's not arbitrary. It's English. In the list [apple, orange, tree] which element is orange? It's the second element. I have taught Python quite a bit, and I have gotten good at explaining 0 based indexing and slicing based on it. When I switched to Julia there was nothing to explain. And my code has about as many +/- 1s as before...
  • jacobolus 8y ago
    Just because it is our common convention in lay conversation doesn’t mean it isn’t “arbitrary”. These spoken language conventions developed before there was an established name for “zero” or even a concept that “nothing” could be a number per se. For similar reasons, we have no zero cards in our decks, no zero faces on a dice, no zero hour on our clocks, no zero year in our calendar, no zeroth floors in our buildings, East Asian babies are born with age one year, etc. It’s only by another set of historical accidents that we have a proper 0 in our method of writing down whole numbers. Thankfully that one was of obvious enough benefit that it became widely adopted.
    • FabHK 8y ago
      > no zeroth floors in our buildings In (North?) America. In Europe, there's a ground floor (zero), then first floor (1), etc. Basement is -1 (etc.). A European friend of mine arrived at college in the USA, and was assigned a room on the first floor of the dorm. She then asked the housing office whether there was a lift, because she had quite some heavy luggage, earning some rather amused looks :-)
      • jacobolus 8y ago
        Yes, it would be interesting to know the history. Whoever designed the European convention for labeling building floors was numerically competent. Too bad medieval European mathematicians and the designers of Fortran weren’t. ;-)
        • Certhas 8y ago
          The base level doesn't need to have a floor, it's just ground. Once you add a floor you are on the first floor above ground. Really your condescending tone as if all the mathematicians that prefer to work with 1 indexing are just incompetent is grating. I'm happy to be writing ``` for i in 1:n func!(a[i]) end ``` to iterate over an object of length n. Or split an array as a[1:m], b[m+1:n]. Slicing semantics which are far more prevalent in my code (and the code I read) than index arithmetic, are truly vastly simplified by 1 based indexing of Julia compared to the 0 based numpy conventions. We simply no longer code in the world that Dijkstra argued for, and I have not seen anybody give a clear argument that is actually rooted in maths and contemporary programming. I genuinely thought that the Python convention was brilliant, and that 1-based indexing in Julia would suck. It turned out not to be the case.
• thousandautumns 8y ago
  Calling the 3rd and 6th columns "3rd" and "6th" is hardly arbitrary.