Talk:Ones' complement

From Wikipedia, the free encyclopedia
Jump to: navigation, search


The entire discussion on binary number systems seems muddled and in need of some organizing and better descriptions of things not 2's complement. This article is intended as a start on that effort. If it passes initial muster I'll continue with cleaning and organizing a couple of closely related pages.

KentOlsen (talk) 22:14, 28 January 2011 (UTC)

One thing that will help it pass initial muster is a quality source that describes the concept. See WP:Reliable Sources for a long and confusing description of what we consider a good source. If you've got that, keep crackin. (p.S. I'm moving this page to conform with the naming guidelines - WP:MOS) The Interior(Talk) 00:44, 29 January 2011 (UTC)
Here's my 2c's worth:
  1. Yes, definitely needs reliable sources - Wikipedia is not the place to write unsourced essays.
  2. According to signed number representations and a lengthy discussion on its talk page, the correct term is "ones' complement", not "one's complement".
  3. The Basics section seems to be plain wrong; surely the whole point of ones' complement is that it replaces subtraction with additon i.e. you do not need to subtract 19, because you add the ones' complement representation of -19 instead.
At the moment, I think that the ones' complement section in the signed number representations article is clearer, more concise and more accurate than this essay. Gandalf61 (talk) 17:09, 30 January 2011 (UTC)

709 representation.[edit]

The statement on the 709 and its derivatives is not exactly true. They used 1's complement in 36 and 72 bit quantities, but 2's complement in 15 bits. Coders had to be aware of this fact in using the AXC instruction on negative quantities. — Preceding unsigned comment added by (talk) 13:52, 28 July 2011 (UTC)


I'm a newbie with wikipedia; but there are others traductions of this page linked between themselves, but not with the english one. Who could resolve it? Mtorrecilla (talk) 11:14, 26 August 2011 (UTC)

Isn't this supposed to be ones' complement (with the apostrophe AFTER the "s")?[edit]

Both Knuth's TAOCP volume 2 and the ISO C standards have it that way, with TAOCP giving the rationale behind it (and why the rule is different for two's complement). Actually, I'm just going to go ahead and change that since Knuth and ISO seem to me to be authoratative. I don't know how to change the page title however, so someone else will have to look into that. It will be a good test on how Wikipedia works :-) — Preceding unsigned comment added by (talk) 14:43, 4 November 2011 (UTC)

I'm with you. Ones' is the complement of a plurality of ones, two's complement is the complement of a singular two. There's a debate about this on the Wikipedia talk:WikiProject Mathematics page where there's a call for more citations for further confirmation. --Matt Westwood 20:18, 4 November 2011 (UTC)
Oh no, I don't need any sources, just someone knowledgeable about the topic. We should move it. Thanks for answering. The Interior (Talk) 02:34, 5 November 2011 (UTC)
I'm only an expert in that I was a professional programmer of LINC, LINC-8, and PDP-12 computers, which were at least in part one's complement computers. I remember that none of the literature associated with these computers used "ones' complement" and all of it used "one's complement". I cannot claim my memory is perfect. While none of the literature is extant, so no citation is possible now, references did exist during the time these computers were sold: the programming manuals. If I ever find a manual in a box in my basement, I'll revisit this page. David Spector (talk) 22:20, 24 July 2013 (UTC)

All moved back[edit]

THis was the text I found inside this page:

This should be the primary article for ones' complement and the "one's complement" should redirect here. The correct "apostrophe after the s" is authoritative from Knuth's TAOCP volume 2 (where the explanation as to why this is so exists) and ISO C99 et al.
However, while I've edited the articles themselves, I'm not confident enough to do the redirection stuff.

Not sure who wrote it. Never mind. I have moved everything back into here, by:

a) Renaming "One's complement" to "One's Complement"
b) Copying everything from "Ones' Complement" into "Ones' complement"
c) Replacing the text in "Ones' Complement" with a redirect to "Ones' complement"
d) Redirecting all the existing redirects to "Ones' complement"
e) Finally, doing this talk page. --Matt Westwood 06:38, 5 November 2011 (UTC)

Requested move[edit]

The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the move request was: Closed early in favor of centralizing discussion at the RfC. Cybercobra (talk) 04:58, 6 November 2011 (UTC)

Ones' complementOne's complement – The spelling issue merits broader discussion. Keep WP:COMMONNAME in mind. --Cybercobra (talk) 09:40, 5 November 2011 (UTC)

And if you actually look at the plurals the apostrophe was ignored in most of them so it actually found "ones complement" Dmcq (talk) 10:01, 5 November 2011 (UTC)
The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Complementing Subtractor[edit]


is it possible for the author to clarify what do you mean by, and quoting, "A complementing subtractor will produce −0 only when both operands are −0."? My question is beause, for me, based on the example of the four subtractions operations on +0 and -0, the result -0 only takes place when operand 1 is +0 (0000 0000) and operand 2 is -0 (1111 1111), and not when both operands are -0 (1111 1111).

Thank you very much for you time.

Best regards,

LuisFilipeM (talk) 16:24, 26 August 2012 (UTC)