Talk:Pi/Archive 2

message: Geometry was a purely axiomatic mathematic until Cartesian thought entered.  You can't claim that these equations are Euclidean, Euclid wouldn't have recognized them.
:They are certainly not from "plane geometry" since some of them talk about three dimensional objects. The "Euclidean" was there to emphasize that there are other geometries where these formulas are wrong. But that point was made earlier already, so I guess we can just call it "geometry". AxelBoldt 03:08 Oct 1, 2002 (UTC)
Concerning this section, I just was thinking about adding a comment after all the volume/area formulae on the Pi page, kind of "all these formulae are in fact a consequence of the second one, as all of them give the volume of solid of revolution (by the formula \pi x \integral...)". I hesitate, because I know that the "pi" page is really a most public place (and thus should be considered almost "locked" for edits, in some sense).
Any comments? — MFH: Talk 00:03, 11 May 2005 (UTC)
thread_title:  Geometry 

message: Am I the only person who gets Main Page edits when following the page history link for π ? I think that the ampersand character may be fucking with the dynamic linking... Perhaps the page should be moved back to Pi? Matt gies 01:24, 5 Mar 2004 (UTC)
thread_title:  Pi's old name 

message: I move that the section on pi culture be moved to a separate article. This article is already getting a bit cluttered and will undoubtedly have more material added to it in the future. As the focus of this particular article is on pi as a mathematical constant, not various mnemomics or "pi day", this may work better at another article. A similar thing was done at the article trigonometric function when the section on mnemomics for the trig functions became rather lengthy and distracting. (I'm not saying to eliminate the section, maybe briefly mention pi day, mnemomics, etc., then give a link.) Discussion?
Revolver 00:10, 13 Apr 2004 (UTC)
thread_title:  Pi culture 

message: Looking at Ramanujan's eqaution for 1/π given in the article,
: \frac{1}{\pi} = \frac{2\sqrt{2}}{9801} \sum^\infty_{k=0} \frac{(4k!)(1103+26390k)}{(k!)^4 396^{4k}} 
it looks like it's possible to simplify the fraction in the infinite sum by removing a k! factor. I think perhaps (4k)! was intended for (4k!). Can anyone confirm or disconfirm this guess? Eric119 01:09, May 28, 2004 (UTC)
Yep, it is (4k)! (looked in the library). Its also already been changed Mrjeff 12:54, 30 Jul 2004 (UTC)
thread_title:  Ramanujan's equation 

message: When did the title start displaying as π ? - Bevo 23:26, 5 Jun 2004 (UTC)
thread_title: Pi article title

message: Shanks' famous calculation of π is listed twice in the history corresponding to two different years, 1853 and 1874.  What's going on there?  4pq1injbok 19:01, 2 Jul 2004 (UTC)
thread_title: Shanks

message: The first two historical values for pi given are both in bold, and so were (presumably) both world records. However, the first one is actually closer to pi than the second. What's going on there?
:They were both in 20th century BC, so maybe it's because we don't know which one came first? ugen64 02:29, Sep 12, 2004 (UTC)
----
I don't understand the recent suppression of
 |mid 6th century BC||1 Kings 7:23||3
by Rossnixon, with "explanation"
  Bible ref would be internal, not external circumference of the vessel
The text is: 
   23 He made the Sea of cast metal, circular in shape, measuring ten cubits
   from rim to rim and five cubits high.
   It took a line of thirty cubits [p] to measure around it. 
As far as I understand, this clearly means: circumference = diameter × 3. Although this is certainly not a candidate for a world record, it might be noteworthy, allows people to discover on-line details of the bible, and besides this, there are other more urgent things ("random joke"...) to delete on this page, imho. — MFH: Talk 12:02, 14 May 2005 (UTC)
replies: text:  More explanation for my deletion, see especially the last paragraph of the article at http://www.uwgb.edu/dutchs/pseudosc/pibible.htm RossNixon 20:41, 14 May 2005 (UTC)
thread_title:  Historical values 

message: I read somewhere that in modern Greek, what we call π is called something else, but I can't for the life of me remember what it was. Does anyone else know, perchance? Gus 04:31, 2005 Jan 3 (UTC)
Maybe something like "number of the circle" in Greek (like the German de:Kreiszahl),
or you may think of "perifereia" (="periphery"), that's where (the initial) π comes from.
(could be mentioned in the introduction...) — MFH: Talk 00:21, 11 May 2005 (UTC)
thread_title:  Greek word for π? 

message: Maybe I missed something, but why not fix up the crummy Pi title, and move the lot to a proper "π" page?
Roy da Vinci 05:25, 13 Mar 2005 (UTC)
thread_title:  π? Pi? 

message: This article claims that pi is both an irrational number and at the same time having a finite length of 1.3511 trillion digits. Both of these claims can not be true, since finite length implies pi being a rational number, which can be expressed as a ratio of two integers:
:\pi = \frac{3 \; 141 \; 592 \; ...}{10^{1 \; 351 \; 100 \; 000 \; 000} } 
--Fredrik Orderud 00:44, 9 May 2005 (UTC)
replies: text:  Thanks, that's a lot better! But my main reason of worrying is the Yasumasa Kanada page, where profesor Kanada, who computed all the digits, claims that "pi has a digit expansion of 1.3511 trillion and does not expand indefinitely as previously assumed". This implies that the 1.3511 trillion digits are all the digits of pi. --Fredrik Orderud 08:50, 9 May 2005 (UTC)
thread_title:  Inconsistency with "irrational number" and "finite length" claims 

message: I don't think that all of the records from 1954 to 1992 were by Wrench and Smith, as the table indicates now.  
A History of Pi by Petr Beckmann, page 197, lists:
1954-1955 NORC is programmed to computer 3089 digits
1957 Pegasus computer (London) computes 7480 places
1959 IBM 704 (Paris) computes 16,167 decimal places
1961 Shanks and Wrench improve computer program for pi, use IBM 7090 (NEw York) t compute 100,000 decimal places
1966 IBM 7030 (Paris) computes 250,000 decimal places
1967 CDC 6600 (Paris) computes 500,000 decimal places
I don't want to change the table (so I don't mess it up again), so I would appreciate it if someone made these changes to the table.  --Bubba73 00:50, 31 May 2005 (UTC)
replies: text: Well, I think I make all of these changes.  --Bubba73 03:29, 6 Jun 2005 (UTC)
thread_title:  calculating records 

message: Sukh, the 70 digits were correct, it would have been enough to click on the link to the  link, in order to verify it! (If even the editors don't use the links to sources...)— MFH: Talk 12:57, 24 Jun 2005 (UTC)
thread_title:  64 or 70 

message: A while back, I created redirects from common approximations (3.14, 3.141, etc). Someone has deleted them. Why? --Celestianpower talk 12:40, 12 July 2005 (UTC)
thread_title:  Redirects