what good is philosophy if you choose arrays based on 1?
https://groups.google.com/forum/?hl=en#!topic/julia-dev/tNN7...
APL, AWK, COBOL, Fortran, Lua, Mathematica, MATLAB, R, Smalltalk, Wolfram
Because it is Mathmatics and have 1 be based on 0 makes no sense, you then have to switch between the two and it is easy to make a mistake. This is why I don't use Python and Pandas. I got burnt once and that was enough and switched to R. Sadly we are stuck with 0 based array in programming and due to a historical issue.
Personally I'm happy to switch between both, and they both have positives and negatives when I actually write code.
0 indexing is not incorrect, or incompatible with maths, it is just a different way of conceiving of lists/arrays by considering the index to more like the distance from the beginning. The first item begins 0 spaces from the start position.
That is why in that context array length is usually the highest index + 1, because length is the distance from the start position to the end of the list, whereas the index is the start position of the item in the list.
I will concede that 0 indexing is a little too close to the storage paradigm for arrays (i.e. a sequential list of items of n bytes) and that when so often these arrays point to more complex data-structures / objects, the distance doesn't make as much sense as the item number... but meh - I'd take Python generators / iterators at the expense of 0 indexing any day.
The problem is that one is indeed an indexing (numbering the contents 1...X...N and asking for item X, customers[X]), whereas the other is not, but is used as an indexing (e.g. customers[5] is not getting the 5th item but the sixth).
If I had to give a name to the concept you're talking about, it would be an "ordinal index".
Which is both the naive understanding of a numeric index in everyday life in general, and the most common case in mathematics (and most math/scientific software).
Although in Wirth inspired languages, actually the indexes are flexible, but by convention 1 gets used.
I really do with the 1 indexing had stayed around, since I feel like it's more natural to say the 1st element, instead of the 0th.
It's not the 0th element. It is the 1st element and has an offset of 0 from the beginning of the array.
Not saying it's better or worse, but that if you change the words you use to describe it, you may find it easier to use.
To my surprise, I just learned that ranges in Rust don't include the end number which felt incredibly stupid from a conceptual point of view (python too). But is syntactically useful when doing:
for x in 0..len(my_array) {
My preference would be that a range include the end number and the language provide more python-like iterators and list comprehensions. I am aware that there is a library that provides more python-like syntax, but that doesn't change the oddness of ranges in either language. I guess I just need to remember that the interval is open on one end. Which brings to mind the notion of using [0..n] or [0..n) in a language...
This is why I think the terminology should be "indexed arrays" and "offset arrays" (and variables perhaps even called index/idx/i or offset/ofst/o as appropriate) instead of using the terms "0-indexed" or "1-indexed."
But I have a hard enough time getting out of the habit myself, and some people are going to hate using o as a variable, so....
If I say `for x in range(10)` it iterates exactly 10 times, starting at zero (which is convenient for 0-index lists in python). It would be extremely counter-intuitive if it did [0,10] as it would iterate 11 times. I agree though that it would be much less ambiguous if you could just do `for x in [0..10)`, for example.
Current implementation requires the least amount of "off-by-one" corrections for most tasks, IMO.
Right and I expect that. The issue I have is that the values do not include 10. It turns out great in Python and Rust where things are 0-indexed, but that does not change the fact that the range construct itself is strange in not including 10.
I'm sure the notion of using mathematical notation where [1..10], (0..10], [1..11), and (0..11) all mean the same thing would drive the language parsing people nuts. Mostly because some of those involve unmatched [) or (]. But that's why we have a computer right?
https://doc.rust-lang.org/std/ops/struct.RangeToInclusive.ht...
It should be indexed with its position then a[1], as we do in all other aspects of life (and in math), and not with it's offset.
You mean like elevators? You may be surprised to learn that elevators in America are 1-indexed (ground floor == floor 1), but in Europe they are 0-indexed (ground floor == floor 0).
In most European countries the ground floor is not considered the same thing as the others. As Wikipedia puts it: "In most of Europe, the "first floor" is the first level above ground level".
We consider and count as floors the "layers" above the ground level. In french for example, the ground level is called "rez-de-chaussée" and the floors above it "XX étage". The ground level is not an "étage" (in American terms, the "ground level" is not considered a floor, and is not counted among the floors).
For this reason, apart from elevator labels nobody calls the ground level "the 0th floor" when speaking/writing.
And even in elevators, O is just used as a convenient way to convey the ground level (since the buttons don't fit much) -- and not everywhere. In many elevators it gets it own designation (e.g. G or GRD or some other national variety).
It's "the ground level" (with different names per country) + "N floors".
A multi-floor building with ground floor + 3 floors can even named "3rd-storey building" in some countries (and the ground level is just taken as granted) -- e.g. une maison à deux étages in the UK --> 3 story building in the US.
I think you just refuted your own previous assertion that 1-indexing is universal in all other aspects of life.
So, no 0-based indexing here.
We call the house a "3-storey house" not because we zero index, but because the cardinality of it's floors (as europeans define a floor) is 3. In "3-storey building" for Europeans, 3 is the "length", not the last index.
It's no more zero-based indexing than naming relations as “sibling”,“first cousin”,“second cousin” is, just because some hypothetical culture that also uses 1-based indexing but counts siblings as first cousins might rationalize our system as starting with “zeroth cousins” where they have “first cousins”.
What they have merely names what Americans name as zero.
But it's not a stand-in for zero, for us, it's a different entity (a different thing).
A floor (etage, piano, orofos, etc) is a "layer of building where people live above the ground level layer".
So there's no zero-based indexing of floors, because the first item in the set of what are considered as floors is called "first" (e.g. primo in italian).
So, the thing one must understand before they say "same difference", is the other cultural difference: that most European countries don't consider the ground level "floor" to be a floor/story.
I.e, we don't consider the upper floors and the "ground floor" to be in the same set. Which is also why we don't count them when we say a "2 story house" (and we mean a house with 3 such layers, ground story + 2 stories).
Is there a zero-based indexing of the whole "heterogenous" set of ground level + floors?
Well, it's common to have the ground level designated with G or national specific names: BG, BV, E, IS, PB, PT, RC, S, P, PK, etc.
It's just that in some elevators 0 is a substitute for this -- which is probably due to the few common brands and parts being international and nobody bothering to change them (e.g. Otis). That's more a red herring than how Europeans think about floors or index them.
So the floors are numbered according to their distance above the ground level (whatever that's called). This matches my suggestion of treating zero-based indexing as a distance from the first element.
>> Is there a zero-based indexing of the whole "heterogenous" set of ground level + floors?
Yes there is! It's how the elevator buttons are labeled with the possible variation of using a label instead of "0".
The European elevator numbering scheme according to your own comments matches more closely with a zero-based indexing scheme than a 1-based. Or more precisely it matches my proposal to consider the numbers used to reference array elements as distances rather than indexes.
It is true that some elevators label the ground level 0, but this is usually when there are also negative levels (cellars).
The German word Stockwerk is even clearer. It describes the wooden planks which separates two levels. So if you live on the first Stockwerk you live one level above ground.
like now with everything 0 based having something like:
arr[offset1 * 32 + offset2]
would be the following if all my offsets would be 1-based and arrays would be 1-based:
arr[(offset1 -1) * 32 + offset2]
which is pretty arbitrary...
My issue is higher level languages Python, Java, C# there is plenty of things that just are complicated and doing arrays off 0 is one of them. Doing data science or statistics just makes it obvious that you have two different sets on numbers. 1 doesn't mean the same thing in every instance in your programming and the functional programming side of me hates that.
https://www.cs.utexas.edu/users/EWD/transcriptions/EWD08xx/E...
Also it's usually a bad sign if you need to worry too much about what index you used, you might be better of using index sets with whatever structure you need (and only the structure you need). In program languages that support it generous application of ranges and generators tends to get rid of most complications.
There is an interesting note in the Wikipedia page for "Dartmouth BASIC" which says the second edition "also allowed arrays to begin as subscript 0 instead of 1. This was especially useful for representing polynomials."
1 + 1 = 2 always means two. When you are getting the 1 column we are getting the second column. This while makes sense when doing certain lower level programming this makes no sense with functional or higher level programming.
Regex and Binary indexes are zero-based, List and Tuple are one-based
iex> [:foo, :bar, :baz] |> Enum.at(1)
:bar
foo = list |> Enum.at(0)
bar = list |> Enum.at(1)
baz = list |> Enum.at(2)
rem = list |> Enum.slice(3..-1)
[foo, bar, baz | rem] = list
I don't recall the details, as this was a long time ago, but there were definitely times I was glad C++ used 0-based arrays, and there were definitely times when 1-based would have made for cleaner code.
So I overloaded the () operator to make a(n), where a is an array, equivalent to a[n-1].
It looked a little odd at first if I mixed a[] and a() form in the same program, but it wasn't hard to get used to.
I doubt I would recommend this in general, but it worked well for this particular application.
I've actually found behaviour of "zero-avoidance" a good battle-tested heuristics to coding. A lot of numeric spaces can be mapped as to be >0 or >0<. Obviously (?) not all of them can, but it's helpful in reducing cyclomatic complexity in logic code, as well as to consumers so they can uniformly handle all falsey values.
Arithmetic is much safer without 0.
if you have array [a,b,c,d] array[0] is a which in computer is logical. why? because it stored in memory 'abcd' (forgetting endianness for sake of argument...) and the offset from the base pointer to a is 0. so it makes perfect sense for arrays to start at 0, as there is no offset from the base... there is not 1 item offset from the base :s if you find it confusing i would say learn how computers actually operate instead of arguing from some theoretical frame of mind which has nothing to do with how computers work. a computer isn't mathematics or some arithmetic machine.
just because arithmetic is safer without 0 doesn't mean it's logical for a computer to suddenly have different array indexing. array indexing on a computer has nothing to do with maths. just memory layout and pointers...
#addsfueltofire
One-based indexing works just as well as 0-based. I've done a lot in the past in Fortran 90 and (regrettably) Matlab. Some things are very slightly harder, some things are very slightly easier. At any rate, this isn't Fortran 77. You shouldn't be fiddling around with indices much.
The bigger difference IMO is Julia uses Fortran-style column-major ordering, instead of row-major like C and Python. I actually
I'd love to see what happens to the tabs vs spaces debate once someone makes tabs that aren't an integer multiple of spaces wide.
So, that world was and is a long time ago. We just don't typically give a way for people to set tabstops in most environments, therefore it was chosen that tabs would advance a certain number of spaces.
integer :: array1(5)
integer :: array2(0:4)
integer :: array3(5:10)
integer :: array4(-4:4)