# Talk:Overline

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## Overline Math Meanings

Hi,

I think it has one more meaning in math: treating to the meaning of an expression as a number made of digits, and not by multiplied variables, for example: ${\displaystyle {\overline {xyz}}}$ means ${\displaystyle x*10^{2}+y*10^{1}+z*10^{0}}$ and not ${\displaystyle x*y*z}$.

Galzigler (talk) 18:19, 2 November 2011 (UTC)

A. I think so too, but haven't found a published example of such usage.
B. I did find a published example of its use as a multiplicative inverse, and added that.
C. It was hard to find all the distinct usages in the math and science section of this article, because some usages had extensive text, and were interspersed among others which had only a single line, so I added labels. A table would be another approach, but the math formatting is so extensive, that adding table formatting would likely induce errors and crowding.
D. Some formulas are indented with colon, causing space. Others are indented with an asterix, causing a bullet. I prefer the space, since the bullet could look like a mathematical symbol and part of the equation to some readers.
E. The Vinculum (symbol) article lists other notations, which should probably be included here, and replaced there with a link to this article's much more extensive list of examples. What do others think?
F. One of the comments below says this article is "about a generic marking and how it may be implemented in text encodings." I would say an encyclopedic article needs to discuss the meanings of the overline marking, not just a "how to" discussion
G. Macron (diacritic) meanings need to be here, since that article is focused on language and simply refers here for mathematical meanings. Macron and overline overlap, because several uses can apply to a single character or string of characters. I don't think the math section needs to distinguish them, though the history and encoding sections need to. Numbersinstitute (talk) 02:50, 25 August 2017 (UTC)

## Doesn't Always Work

This article has some issues. The unicode technique listed here for macrons does not work in Word or perhaps it only works in specific fonts. "The character U+0305 ◌̅ combining overline allows an overline to be placed over any character (as with any combining character, it appears over the preceding character: for example, x̅, compared to x‾). A series of overlined characters usually results in an unbroken line, depending on the font (for example, 1̅2̅3̅)." This does not work in Arial or Arial MS Unicode. --Pfstevenson32 (talk) 15:23, 16 June 2013 (UTC)

## Vinculum (symbol)

It is another name for overline and doesn’t represent a distinct concept. By the way, the macron is a distinct concept, but (thanks to ISO and Unicode great experts on typography) our character repertoire and names are now inflated, conflated, and tangled, possibly beyond repair. Incnis Mrsi (talk) 08:36, 23 March 2014 (UTC)

Oppose: As stated in the lead, "or alternatively it may function as a binary connective between arguments appearing above and below it." So it is not merely another word for overline. However, Overline might possibly be merged into vinculum, or material on the two pages could possibly be distributed differently.-- (talk) 09:32, 23 March 2014 (UTC)
LoL. How the vinculum’s use as a binary operation could preclude its merger into “overline”? Incnis Mrsi (talk) 10:59, 23 March 2014 (UTC)
May I add that I also mildly oppose your use of language in talk posts and edit summaries (sample: Laugh out Loud / confusion and ignorance / useless / careless editing / removing idiocies / imbecilities / typographic obscurantism). I don't think that helps making wikipedia a better encyclopaedia in the long run.-- (talk) 18:27, 23 March 2014 (UTC)
Opposed: Nominally, vinculum is a specific symbolic notation; that is, "bind together". Overline is a type of mark that may have specific symbolic meanings in contexts, one of which is "bind together". The two articles have different core purposes; one about a specific historical symbol, the other about a generic marking and how it may be implemented in text encodings. This is not to say I have no problems with those articles; see Talk:Vinculum (symbol)#All that lines is vinculum?.
My opinion is that the problem is not a need to merge; rather, the problem is a need to more clearly separate. Vinculum (symbol) should be the place to discuss the vinculum symbolic notation, its history, and legacy (e.g., square root symbol), and remove or qualify which horizontal line symbols have no relation to vinculum other than superficial appearance.
Overline should only reference Vinculum (symbol), not merge with it. Someone should work up any Vedic origin of overscore marking for Negation and Subtraction or maybe even large Roman numerals, add that to those articles and then have Overline only link to that work. If you are looking for something to do, there is a lot more work there.
Both articles need clean up, and I think Vinculum (symbol) needs the attention of an expert. Merging would only perpetuate and aggravate the existing problems with both pages, especially where Wikipedia may be the only source that links vinculum to some uses. (see Talk:Vinculum (symbol)#Is a fraction bar a vinculum?.
Not every overscore is a vinculum; and I’m not sure if every form of a vinculum is an overscore. IveGoneAway (talk) 23:33, 24 March 2014 (UTC)
Vinculum is a more specific term than overline. In my view there is enough to say specifically about the term vinculum for it to deserve its own entry. Crisperdue (talk) — Preceding undated comment added 17:05, 14 August 2014 (UTC)
Opposed: As others have noted, not every overscore is a vinculum and the reverse may also be true; the problem is that the vinculum article has a grand total of one citation for anything on it, and as its talk page mentions it appears that at least some of the material cannot be sourced to elsewhere. Werhdnt (talk) 18:10, 13 September 2014 (UTC)
Strongly Opposed: Contrary to an opinion expressed above, an overscore and a vinculum are not the same thing. A vinculum is, and has historically been, a way to express that some symbols are aggregated (grouped together as in forming a unit). A vinculum does not have to be an overscore, there are several instances where an underscore was used as a vinculum. The use of a vinculum predates the use of parentheses for the same purpose and it is the advent of movable type that has swung the preference for parentheses over vincula. The vinculum (symbol) article has been corrected and this article needs to be purged of this mistaken idea that every overscore is a vinculum. Bill Cherowitzo (talk) 18:43, 25 March 2015 (UTC)