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Numbering should start at zero (1982)

cs.utexas.edu

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Re: Numbering should start at zero (1982)

#101

Post by personalaccount »

roenxi wrote: post #3

The 1980s were not a particularly enlightened time for programming language design; and Dijkstra's opinions seem to carry extra weight mainly because his name has a certain shock and awe factor. It isn't usual for me to agree with the mathematical convention for notations, but the 1st element of a sequence being denoted with a "1" just seems obviously superior. I'm sure there is a culture that counts their first fing…

> The 1980s were not a particularly enlightened time for programming language design; and Dijkstra's opinions seem to carry extra weight mainly because his name has a certain shock and awe factor.

Zero based indexing had nothing to do with Dijkstra's opinion but the practical realities of hardware, memory addressing and assembly programming.

> I'm sure there is a culture that counts their first finger as 0

Not a one because zero as a concept was discovered many millenia after humans began counting.

Re: Numbering should start at zero (1982)

#102

Post by theoreticalmal »

School-Cotton wrote: post #81
nivertech wrote: post #43

Numbering should start at π (2025) (umars.edu) Seriously, it all depends on whether u're counting the items themselves (1-based) or the spaces btwn them (0-based). The former uses natural numbers, while the latter uses non-negative integers For instance, when dealing with memory words, do u address the word itself or its starting location (the first byte)? The same consideration applies to coordinate systems: r u pos…

Why do you write “you” as “u” here? I don’t want to be rude, but it’s very jarring to see juvenile txt-speak in a serious discussion.

“serious discussion” notwithstanding, I thought the “u’re” was particularly interesting. Why not “ur”? “u” is obviously easier to write, so why worry about properly contracting it? Just interesting imo

Re: Numbering should start at zero (1982)

#103

Post by y42 »

nivertech wrote: post #43

Numbering should start at π (2025) (umars.edu) Seriously, it all depends on whether u're counting the items themselves (1-based) or the spaces btwn them (0-based). The former uses natural numbers, while the latter uses non-negative integers For instance, when dealing with memory words, do u address the word itself or its starting location (the first byte)? The same consideration applies to coordinate systems: r u pos…

I totally disagree, but it's only my opinion and probably not scientific at all.

From a logical point of view I think it's totally unnatural to start at 1. You have 10 diffferent "chars" available in the decimal system. Starting at 1 mostly leads to counting up to 10. But 10 is already the next "iteration". How do you explain a kid, who's learning arithmetics, that the decimal system is based on 10 numbers and at the same time you always refer to this list from 1 to 10.

Re: Numbering should start at zero (1982)

#104

Post by mdiesel »

01HNNWZ0MV43FF wrote: post #84
Aransentin wrote: post #46

Perhaps ideally we'd change English to count the "first" entry in a sequence as the "zeroth" item, but the path dependency and the effort required to do that is rather large to say the least. At least we're not stuck with the Roman "inclusive counting" system that included one extra number in ranges* so that e.g. weeks have "8" days and Sunday is two days before Monday since Monday is itself included in the count. *…

It is definitely my engineer myopia, but octaves in music should be called dozens

I think we should call them doubles

Re: Numbering should start at zero (1982)

#105

Post by Y_Y »

School-Cotton wrote: post #41

1-based numbering is nonsense. How many years old are you when you’re born? I notice almost all defenses of 1-based indexing are purely based on arbitrary cultural factors or historical conventions, e.g. “that’s how it’s done in math”, rather than logical arguments.

> How many years old are you when you’re born?

Consider the following from the Irish Constitution:

> 12.4.1° Gach saoránach ag a bhfuil cúig bliana tríochad slán, is intofa chun oifig an Uachtaráin é.

and the official translation to English:

> 12.4.1° Every citizen who has reached his thirty-fifth year of age is eligible for election to the office of President.

For those unfortunate few who do not understand Irish, that version says "Every citizen who is at least thirty-five years old", whereas the translation should in principle (arguably) allow a thirty-four-year-old.

Luckily the Irish version takes precedence legally. A constitutional amendment which would have lowered the minimum age to 21 and resolved the discrepancy was inexplicably rejected by the electorate in 2015.

Re: Numbering should start at zero (1982)

#106

Post by InsideOutSanta »

sim7c00 wrote: post #68
InsideOutSanta wrote: post #54

Earlier quoted context omitted.

It's interesting how most people find learning 0-based indexes confusing, but after a few years of programming, they don't even notice how odd it is. How do you number things in real life? If you have two options, do you number them "option 0" and "option 1" or "option 1" and "option 2"? If you create a presentation with numbered bullet points, do you start numbering them from 0 or 1? 1. This is my first point 2. Thi…

if you see how its implemented in machine code (on most modern archs) you will see how it is logical. once you see that, you cannot unsee it. people call these things an index, but really it is an offset from the base of the array. not an index into it. hence, base + 0 is the first entry. as the offset to that entry is 0. thats how it will work in generated machine code on all the machines i saw (i did not see all of…

Yes, it's the offset from a pointer in some languages. But to the user, it's presented as an index, not an offset. In normal syntax, you don't access an array value using a construct like

*(arraypointer+offset)

If you did that, then using 0 as the start offset would make intuitive sense.

In fact, if not for this technical reason, I doubt that any programming language would have 0-based indices.

Re: Numbering should start at zero (1982)

#108

Post by nivertech »

01HNNWZ0MV43FF wrote: post #83
nivertech wrote: post #43

Numbering should start at π (2025) (umars.edu) Seriously, it all depends on whether u're counting the items themselves (1-based) or the spaces btwn them (0-based). The former uses natural numbers, while the latter uses non-negative integers For instance, when dealing with memory words, do u address the word itself or its starting location (the first byte)? The same consideration applies to coordinate systems: r u pos…

That makes sense for the ID system or a database, but for arrays in a language I still prefer starting at 0. It makes frame buffers easier easier to index

I prefer thinking from the first principles, and not according to the current computer architecture fashion.

And BTW that ID system was used in the system processing PBs of data in realtime per day back in the early 2000s, so it’s not that it was super-inefficient.

Re: Numbering should start at zero (1982)

#109

Post by Y_Y »

golol wrote: post #38

Consider n real numbers a_0, ..., a_{n-1}. That's not very elegant.

Sure it is.

This discrepancy appears in physics too. It's common to use 1,2,3 for spatial indices, but when you reach enlightenment and think in terms of spacetime you add a zero index and not a four.

Re: Numbering should start at zero (1982)

#110

Post by mixmastamyk »

slightwinder wrote: post #56
pansa2 wrote: post #27

Earlier quoted context omitted.

It makes more sense if you think of indices as pointing between elements: 0 1 2 3 4 ----------------- | A | B | C | D | ----------------- -4 -3 -2 -1 -0 Except, of course, -0 doesn't exist. AFAIK that's why C# chose to add a special "index from end" operator, `^`, instead of using negative indices.

Your visualization makes sense if you always count them going from left to right. But with negative index you naturally count them going from right to left, from the last element backward to the first element. So -0 is the natural starting-point, except it's -1 in python.

-1 is correct, there is no -0. The math works correctly the Python way.
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