Talk:Ordinal number
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Ordinal number has been listed as a good article under the good-article criteria. If you can improve it further, please do. |
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[edit] GA Re-Review and In-line citations
Members of the Wikipedia:WikiProject Good articles are in the process of doing a re-review of current Good Article listings to ensure compliance with the standards of the Good Article Criteria. (Discussion of the changes and re-review can be found here). A significant change to the GA criteria is the mandatory use of some sort of in-line citation (In accordance to WP:CITE) to be used in order for an article to pass the verification and reference criteria. Currently this article does not include in-line citations. It is recommended that the article's editors take a look at the inclusion of in-line citations as well as how the article stacks up against the rest of the Good Article criteria. GA reviewers will give you at least a week's time from the date of this notice to work on the in-line citations before doing a full re-review and deciding if the article still merits being considered a Good Article or would need to be de-listed. If you have any questions, please don't hesitate to contact us on the Good Article project talk page or you may contact me personally. On behalf of the Good Articles Project, I want to thank you for all the time and effort that you have put into working on this article and improving the overall quality of the Wikipedia project. Agne 05:48, 26 September 2006 (UTC)
[edit] Division undefinable?
From the article:
One can define addition, multiplication, and exponentiation on ordinals, but not subtraction or division.
This seems to be contradicted by the MathWorld article on ordinals[1], which gives as an example:
where r is a real number. How is this to be explained? Simões (talk/contribs) 05:28, 25 November 2006 (UTC)
- My first reaction was, in general, don't be surprised if you see nonsense on MathWorld. That's maybe a little unfair; their actual common sin is more promoting neologisms as though they were standard usage, which I guess isn't quite as bad as actual false statements.
- In this case, though, there's nothing wrong with what they actually wrote. You need to look at it a little closer. That isn't a fraction sign, and r is presumably not an (arbitrary) real number. --Trovatore 05:57, 25 November 2006 (UTC)
- What you saw there is NOT an underline indicating division, it is a brace indicating that there are r copies of ω being added together to get ω·r . JRSpriggs 09:07, 25 November 2006 (UTC)
