# Talk:One half

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## Other fraction pages

This is the only page on a fraction that I intend to create. But if others create pages on other fractions, such as the ones that get code points in the Unicode Number Forms block, and are in common use, I would be glad to work on those. Fractions that approximate π are probably best only mentioned in the article on π. PrimeFan 17:12, 11 Feb 2004 (UTC)

## Floating Point Quandary

I will eventually figure out how to write 1/2 in single precision floating point. If someone knows how to do it, please add it to this page, but please don't tell me directly, I want to figure it out on my own. PrimeFan 17:12, 11 Feb 2004 (UTC)

User:Toby Bartels added the floating point a few months ago. More recently, a well-intentioned rookie user added some unlikely precision errors. I've seen glitches in calculators and computers, but no calculator or computer has ever told me that 1/2 = 0.4999999... Since two is divisible by the base numbers of the common bases we humans regularly use (binary, octal, decimal and hexadecimal) I see no need to list unlikely precision errors. If we do a page on 1/3 or 1/7, that's a different story. Anton Mravcek 17:59, 30 Jun 2004 (UTC)
I don't think those were intended to be values with error. They are proper alternate representations of 1/2 in a place value system: the binary one, for instance, holds because the sum of the geometric series ${\displaystyle \sum _{n=2}^{\infty }2^{-n}=1/2}$. 4pq1injbok 01:56, 1 Jul 2004 (UTC)
4pq1injbok might be new here, but he knows what he's talking about. I tried putting in the left side of that equation into Mathematica 4.2 and sure enough it replied 1/2. Then to N[%], it replied 0.5. So if there are no further objections from you, Anton, I will restore the "unlikely precision errors" to the Docuan table. PrimeFan 21:25, 1 Jul 2004 (UTC)
I still don't see where the 0.49999999... comes from. Anton Mravcek 22:39, 1 Jul 2004 (UTC)
I see there's been some discussion of this at Talk:Cantor's diagonal argument. Perhaps we should create the page alluded to there on numbers with two different decimal expansions. 4pq1injbok 23:58, 1 Jul 2004 (UTC)
Fascinating. I will print out that page and do some serious thinking on it. Anton Mravcek 20:49, 6 Jul 2004 (UTC)

## Latin prefixes for fractions

I know the Latin numerical prefixes for whole numbers 1-1000, but does anyone know about fractions?? The most well known are 1/2 (semi-) and 3/2 (sesqui-) Any others anyone knows?? 66.245.123.29 18:55, 24 Nov 2004 (UTC)

• The most well known certainly is "semi-" for 1/2. I had never even heard of "sesqui-" for 3/2. There probably are prefixes for other common fractions like 1/4 and 1/3, but these are probably so obscure as to have no practical value. If you do learn them, it would be nice to add them to Wikipedia, probably at [[fraction]] or something like that. (1/4 and 1/3 might merit their own pages, but anyone thinking of creating an article on them should have enough information to create something more than a stub). PrimeFan 19:10, 24 Nov 2004 (UTC)

## Requested move to ½...

One half½ – ½ is in ISO 8859-1, and more people would want to link [[½]] than [[One half|½]] — KelisFan2K5 12:51, 31 Mar 2005 (UTC) I think we should move this to ½ because

• It's in ISO 8859-1, so that shouldn't be a problem
• More people will want to write [[½]] instead of [[One half|½]]
Add *Support or *Oppose followed by an optional one sentence explanation and sign your vote with ~~~~

### Support

• Support - and provided we keep the redirects, it definitely won't be a problem. Warofdreams 16:22, 31 Mar 2005 (UTC)
• Support - it would solve the issue below of referring to the article as "one half" (rather than "a half", or simply just "half"). edam (talk) 10:45, 20 April 2011 (UTC)

### Oppose

• Oppose - There is already a redirect from ½ so this is not a problem -- Philip Baird Shearer 16:37, 31 Mar 2005 (UTC)
• Oppose - 'One half' can be entered in the go and search boxes; shooting myself down: if the redirects are in place that shouldn't matter Josh Parris 23:29, 31 Mar 2005 (UTC)
• Oppose The reasons for the move are already supported by redirects. The title is a formal usage, so spelling out the words "one half", or maybe even "half", seems more appropriate to me (as has been done in Pi and square root). Michael Z. 2005-04-1 00:03 Z
• Opppose. ASCII link is so much nicer than an ISO thingie. Also, I saw people at PlanetMath putting formulas and all kind of things liberally into article names, and looks terrible. Oleg Alexandrov 01:32, 1 Apr 2005 (UTC)
• Oppose. Still looking for something—that isn't my antique Underwood typewriter—with a ½ key on it. That and full concurrence with what Michael said.—ExplorerCDT 06:22, 1 Apr 2005 (UTC)
• Being difficult for you to type doesn't make it wrong (but the other thing does). Michael Z. 2005-04-1 06:50 Z
• Thorn (letter) was recently moved to Þ, would that be better at Thorn (letter)? Also, Ð was at Eth (letter). And, ÆAE ligature, ØO-slash. --KelisFan2K5 13:16, 1 Apr 2005 (UTC)
• I'll vote to support a name change for an article to be named ½ when my keyboard brings the key back. That and the ¢ key which the absence of I lament very much. It's not me being difficult, it's just practical. There's no use wasting time having to hunt and peck around the character map just to locate the article without a redirect when I could have typed "one half" about twenty times. Until then, I'll just keep writing "one half" and "cent" everytime the symbol would have been easier to type had my keyboard retained the key. As for Thorn (Þ), who cares? I doubt anyone other than an old english/anglo-saxon nut would even know what the letter was anyway. —ExplorerCDT 14:53, 1 Apr 2005 (UTC)
• Why is going to the article without a redirect so important? Michael Z. 2005-04-1 17:03 Z
• Oppose. Redirects are a great convenience for the reader, of course, but it is preferable to minimize the need for them because they consume server resources when a reader is bounced from the redirect to the article. Cummulatively, this adds up. Also, whenever possible it is preferable to have article names in characters available on most English language keyboards. Jonathunder 21:57, 2005 Apr 1 (UTC)
• Having non-redirecting links have benefits, but so do redirects. Anyway, we're not going to rename articles just to reduce a few redirecting links. Michael Z. 2005-04-1 22:09 Z

It was requested that this article be renamed but there was no consensus for it to be moved. violet/riga (t) 09:03, 4 Apr 2005 (UTC)

## one... half????

"One half" sounds so wrong to me. "One" here is redundant. Just saying half has the same meaning and it's not like you'd say "Two halves" or "Three halves". It sounds strange to hear "one half" on US tv shows. (I've never heard a british english speaker use the term.) "one half" itself sounds like an oxymoron to me. Doesn't it lead to confusion? I can imagine people mishearing and thinking "1 and a half".

On a related note, I think there's a "one hundred" (U.S.) vs "a hundred" (U.K.) split across the two types of English. I'm sure it's not too confusing to say "one half" without sounding like "one and a half", provided "and" is not reduced too much. Americans would probably have better answers to this though... -- the GREAT Gavini 18:02, 19 September 2006 (UTC)

Yeah, but one half still sounds odd. I think you're right in that mostly "a half" would be used if it was needed. However, Americans say "a half hour" (Where generally british english speakers would say "half an hour") which seems to break the trend. With other fractions in British english they're a/an "a seventh", "an eighth".
Yeah, i agree one half sounds a little wrong, cos clearly there exists two halves in this world, and half shouldn't be taken singular. "Other Halves". Men. —Preceding unsigned comment added by 130.216.1.16 (talk) 06:52, 15 September 2008 (UTC)

## 2 ½ with or without space

Typographically, what is best 2½, 2 ½ or 2 ½? TIA.--Hhielscher 09:42, 4 December 2006 (UTC)

Is a hyphen required?

Should it be one half or one-half? Origen (talk) 16:18, 10 March 2009 (UTC)

## Cleanup

I have removed a fair amount of extraneous information:

• the repeating expansions in the infobox
• the floating-point representation in the infobox
• the paragraph beginning "One half has two different decimal expansions...".

While it's true that 0.4999... is equal to 0.5 (per the same arguments as in our 0.999... article), I don't believe anyone ever thinks of 0.5 in this way. Indeed I believe that belaboring this point (and in not one but four different bases!) is much more likely to confuse readers than enlighten them.

That is, while the statement "one half has two different decimal expansions" might be true in some rarefied stratum of numerical analysis, in everyday usage (and indeed in everyday mathematical usage) I believe it is absurd and simply false.

In a similar vein, I don't believe it's useful to list a floating-point representation here. If you're trying to understand a particular floating-point format (of which there are many), knowing how 0.5 is represented in it is certainly interesting and relevant, but to pick just one of those formats and present it here as if it's one of the representative forms of one half is, again, uninteresting at best and misleading at worst.

Well, User:Wcherowi didn't agree with any of those changes, and reverted them all, but didn't explain why. I'm curious to know what other editors think. Take your mathematician and/or editor hat off and think like a reader who's coming here to learn something. Does it really tell you anything you need to know to see that the decimal expansion is "0.5 or 0.499999999999..."? Or that the "Single-precision floating point" representation is 3F000000? —Steve Summit (talk) 04:21, 14 February 2015 (UTC)
To set the record straight, I do agree with your assessment of the floating point representation and most likely would have come back to the page to remove it. I could also agree that having so many examples is a bit of overkill and could use some trimming. What I strongly objected to was the removal of any indication that there are alternate representations. If a reader is coming to this page to learn something, then that is a good thing to learn. I have faced far too many students unwilling to accept the equality of 1 and 0.99999... even after several explanations with various degrees of rigor. Some who are finally convinced, walk away with the impression that it is a one off phenomena, applicable only to the number 1. More exposure to the concept, in several settings is what is called for. You may wish to argue that this information is not encyclopedic – I would disagree – however, a quick glance at any of our many pages on specific "boy bands" will soon disabuse you of the notion that all content on WP is encyclopedic in nature. As to the multiple representations in different bases, I also think that this is worth noting, at least for the more sophisticated reader who may turn up on this page. As a final thought, I think that it is naive to believe that readers would come to a page such as this to learn about the concept, rather it is curiosity about what we would say about it that would bring them here, and we should not disappoint by having nothing on the page that they don't already know. Bill Cherowitzo (talk) 05:36, 14 February 2015 (UTC)
Fair enough; thanks. —Steve Summit (talk) 12:07, 14 February 2015 (UTC)
For me there's a disconnect -- which I am trying to figure out how to articulate -- between (a) saying "0.999... is equal to 1" (which is very true, not necessarily obvious, and important to explain to people who may misunderstand or deny it), and (b) stating that one, or one half, or two and a half, or three (or indeed any number which does not have a single, recurring expansion) "has two expansions". It's sort of an undue weight thing. As a thought experiment, if a student (at almost any level, in almost any context) were asked for the decimal expansion of one half, and answered "0.4999...", I don't think they'd be marked correct, so it bothers me to suggest that the two expansions are equally "right". But I do take your point that repeated exposure to the concept can be pedagogically useful, so I'm forced to admit that presenting it as an example here (even in, dangit, multiple bases) isn't necessarily a bad thing. —Steve Summit (talk) 12:30, 14 February 2015 (UTC)
In your thought experiment, the fact that the 0.4999... response would, more frequently than not, be considered incorrect is a sad commentary, and not one on the student. In a more perfect world, in which the understanding of things mathematical was not just skin deep, this topic would require no more than a passing aside. But we don't live in such a world and I don't feel too bad about erring on the side of pushing a concept a bit harder than it deserves – provided it isn't done too often and is done with a bit of wit and grace. Bill Cherowitzo (talk) 23:24, 14 February 2015 (UTC)