Talk:Tuple

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Contents 1 Alternative definition 2 Proposal to split article 3 Computer science meaning 4 Move from N-tuple to tuple 5 Anyone notice... 6 suggest change 7 Usage in computer science 8 100tuple 9 Singleton 10 Proposal to Remove "Usage in Computer Science" 11 "Up tuples" and "down tuples" 12 Couple, coupling 13 Need for a disamb?

[edit] Alternative definition

an n-tuple can be defined in terms of sets as (a1,a2,...,an)= {a1,{a1,a2},{a1,a2,a3},...,{a1,a2,...an}}

Would that not give the same for (1,2,1) and (1,2,2)? - Patrick 11:01 Mar 30, 2003 (UTC)

---

Yes it would. At least the inductive definition seems to be able to cope with duplicate elements without losing information.

[edit] Proposal to split article

Would anyone object if I would split the article in tuple (mathematics) and tuple (computer science)? I believe their usage is different enought to warrant that. Apart from that I find the term n-tupel a bit odd, and it is one I have not heard as such very often. -- Jan Hidders 01:07, 17 Feb 2004 (UTC)

[edit] Computer science meaning

The usage of tuples in computer science, as described in the article (where "components are identified by a unique field name and not by a position"), is not entirely correct. The Python programming language, for example, has a tuple datatype where components are referenced by their position. It also has a datatype where components are referenced by a unique name, however this is called dictionary. In other languages such a structure is also known as an associative array or a hashtable.

True. But note that it doesn't say that this is how the term is always used in computer science. Guido, being the mathematician that he is, uses the term in its mathematical meaning and I as a computer scientist also very often do. However, if you look into the scientific literature on the theory of programming languages and database theory you will see that this is the standard definition. And of course, as is usual in computer science, people will give it their own meaning as they see fit. Even so, you are right that these usages should be reflected in the article. Note, btw, that associative arrays are not always the same as tuples because in PHP, for example, they do have a notion of position. And a hash table says something about how it is implemented, and is therefore also not exactly equivalent. -- Jan Hidders 09:18, 17 Feb 2004 (UTC)

This definition indeed doesn't seem right. Here's the one on Foldoc: http://wombat.doc.ic.ac.uk/foldoc/foldoc.cgi?tuple Fredrik 18:04, 27 Feb 2004 (UTC)

What I find disturbing, is the example. In particular "Note that the order of the components is not relevant" ... in Python, the order is very important ... does this show up in computer science literature as a definition? If not I highly recommend removing someone's opionion of what a tuple is as shown in the example. -- Mwtoews Tuesday, April 11, 2006 at 20:14:01

[edit] Move from N-tuple to tuple

The n in the title could just as well have been any other letter. It has no significance. I suggest we move this page to tuple. Unfortunately history exists there so I can't do it. --MarSch 15:28, 19 May 2005 (UTC)

• Support. James F. (talk) 16:34, 19 May 2005 (UTC)
• Support. Jitse Niesen 10:32, 20 May 2005 (UTC)
• Weak oppose. If we're using common names, I've always come across this as an "n-tuple", not a "tuple". Yes, n could have been any other letter, but it is the standard as far as I am aware: no one says "p-tuple" or "g-tuple". Merriam-Webster has no entry for "n-tuple", but lists "tuple" as a suffix, "-tuple", not as an independent word. MathWorld's entry is at "n-tuple". — Knowledge Seeker দ 13:35, 20 May 2005 (UTC)

This article has been renamed as the result of a move request. violet/riga (t) 14:45, 24 May 2005 (UTC)

[edit] Anyone notice...

That this article is just a shortened version of this?

Did you notice :"The source of this article is Wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL." at the bottom? --MarSch 1 July 2005 10:14 (UTC)

[edit] suggest change

Am I the only one who thinks, that

if (a1, a2,...) = (a1, (a2,...)) then (1, 2, 2) = (1, (2,2)) = (1, (2), (2)) I really don't understand the reasoning that makes this into

(1,(2,(2,()))) = (1,(2, {{2}, {2, ∅}} )) = (1, {{2}, {2, {{2}, {2, ∅}}}} ) = {{1}, {1, {{2}, {2, {{2}, {2, </nowiki>∅}}}}}} in the "formal definitions" part in the middle. It seems to me like a copy-paste error.

Silencer1981 10:55, 7 September 2006 (UTC)

(1,2,2) = (1,(2,2)) = (1,(2,(2))) = (1,(2,(2,()))). At each stage you take the innermost tuple and separate the first item from the remainder of the tuple. This finishes only when the innermost tuple has no first item i.e. when it is the empty tuple. EdC 22:25, 21 October 2006 (UTC)

[edit] Usage in computer science

The section says tuples have "three distinct meanings". I'm having difficulty finding more than two. Are the records defined in the first paragraph distinct from the sort of tuples Eiffel has? Those two are clearly distinct from the associative array usage.

Also, I'm not exactly clear on how the Python notion of tuples as immutable lists is related to the notion of records here. If anyone can clarify these points, I'd appreciate it.Chris Johnson 23:43, 10 March 2007 (UTC)

[edit] 100tuple

This is obviously incosequential but I was under the impression that 100-tuple in a joke like manner is called a "hectic". Cetuple is also right as it is just the normal english latin-based multiple word. I currently have not the time to reference that. anyone familiar with it? —Preceding unsigned comment added by Squidonius (talk • contribs) 00:18, 16 November 2007 (UTC)

[edit] Singleton

As I understand the formal definition, the 1-tuple (x) is really:

This is technically different from the singleton {x} —Preceding unsigned comment added by 68.84.9.196 (talk) 18:29, 7 July 2008 (UTC)

[edit] Proposal to Remove "Usage in Computer Science"

This section is not about computer science, rather, it is about computer programming languages. The usage of tuples in computer programming languages itself does not seem notable, since programming languages that support tuples define them in exactly the same way as the mathematical definition. If they don't, then they don't support tuples. That itself may be notable, but there are no sources here to reference. For example, the discussion about "field names" describes a structure called "tuple", but it does not meet the criteria of a tuple according to this article. It is just misleading. Same story for the information modeling "tuple". Merely demonstrating examples of tuples in different programming languages (Eiffel, Python) does not belong on this page, rather, in the articles for those languages. --Beefyt (talk) 22:41, 9 July 2008 (UTC)

I have removed most of this section, retitled it "Relational model", and added a reference. --66.162.32.234 (talk) 16:20, 10 July 2008 (UTC)

[edit] "Up tuples" and "down tuples"

There's a book called "The Structure and Interpretation of Classical Mechanics," which proposes that there are two kinds of tuples: "up" tuples, and "down" tuples. The only explanation provided about the difference between them is that one of them is surrounded by parentheses, while the other is surrounded by square brackets.

Has anyone ever heard of "up tuples" and "down tuples"?

The book is strongly associated with a computer algebra system called SCMUTILS, which returned a "down tuple" of the following expressions when I took a derivative:

98.31.14.215 (talk) 03:54, 31 August 2008 (UTC)

[edit] Couple, coupling

Term for 2-tuple, relationship? --Fgrose (talk) 20:20, 16 March 2009 (UTC)

[edit] Need for a disamb?

Someone recently added to the artcile an "about" template that had a red-link to "tuple (disambiguation)". The editor was apparently planning to create an article on tuple (Python). Without thinking twice, I tried to be a good citizen and created a tuple (disambiguation) page. But now the link has been removed from tuple, so tuple (disambiguation) is an orphan; and tuple (Python) hasn't materialized yet. Should I ask for its deletion? All the best, --Jorge Stolfi (talk) 22:28, 26 June 2009 (UTC)

I'm a huge Python fan, but its tuple datatype doesn't deserve its own article; it and tuples in other languages are essentially the same as the object described in the current article. You can probably WP:CSD the disambiguation page. --Cybercobra (talk) 22:53, 26 June 2009 (UTC)