|
Author
|
Topic: How do you calculate Pi?
|
Minnemooseus
Member Posts: 3944 From: Duluth, Minnesota, U.S. (West end of Lake Superior) Joined: 11-11-2001 Member Rating: 10.0
|
|
Message 1 of 10 (129057)
07-30-2004 11:14 PM
|
|
|
This is vaguely a spin-off of message 68 of the PROOF OF GOD topic. So, how DO you calculate Pi? Moose
| Replies to this message: | | | Message 2 by Coragyps, posted 07-30-2004 11:37 PM | | Minnemooseus has not replied | | | Message 6 by bob_gray, posted 07-31-2004 12:29 AM | | Minnemooseus has not replied | | | Message 7 by fnord, posted 07-31-2004 5:58 AM | | Minnemooseus has not replied |
|
Coragyps
Member (Idle past 753 days) Posts: 5553 From: Snyder, Texas, USA Joined: 11-12-2002
|
Er..., um...... I once knew that one! You add up some infinite series of fractions: the series for e, the base of natural logarithms, is 1 + 1/1 + 1/2! + 1/3! + 1/4! +.... you get my drift..... But I don't remember the series for pi. Sorry. But I was sorrier when I calculated it myself to eight or so decimal places - it was before electronic calculators, and only shortly after the invention of the #2 pencil.
| This message is a reply to: | | | Message 1 by Minnemooseus, posted 07-30-2004 11:14 PM | | Minnemooseus has not replied |
|
jar
Member (Idle past 413 days) Posts: 34026 From: Texas!! Joined: 04-20-2004
|
|
|
Message 3 of 10 (129062)
07-30-2004 11:51 PM
|
|
|
Measure the circumference of a circle and divide that by the diameter.
Aslan is not a Tame Lion
| Replies to this message: | | | Message 4 by Coragyps, posted 07-30-2004 11:54 PM | | jar has replied |
|
Coragyps
Member (Idle past 753 days) Posts: 5553 From: Snyder, Texas, USA Joined: 11-12-2002
|
|
|
Message 4 of 10 (129063)
07-30-2004 11:54 PM
|
Reply to: Message 3 by jar
07-30-2004 11:51 PM
|
|
But use the GOOD ruler to measure.
| This message is a reply to: | | | Message 3 by jar, posted 07-30-2004 11:51 PM | | jar has replied |
| Replies to this message: | | | Message 5 by jar, posted 07-30-2004 11:55 PM | | Coragyps has not replied |
|
jar
Member (Idle past 413 days) Posts: 34026 From: Texas!! Joined: 04-20-2004
|
|
|
Message 5 of 10 (129064)
07-30-2004 11:55 PM
|
Reply to: Message 4 by Coragyps
07-30-2004 11:54 PM
|
|
But use the GOOD ruler to measure. The one in sacred millimeters? 
Aslan is not a Tame Lion
| This message is a reply to: | | | Message 4 by Coragyps, posted 07-30-2004 11:54 PM | | Coragyps has not replied |
|
bob_gray
Member (Idle past 5032 days) Posts: 243 From: Virginia Joined: 05-03-2004
|
using the arctan
One way is to use the formula: arctan(x) = x - (x^3/3) + (x^5/5) - (x^7/7) + ..... combined with the fact that arctan(1) = Pi/4 Gives the formula: Pi = 4(1 - (1/3) + (1/5) - (1/7) + .....)
| This message is a reply to: | | | Message 1 by Minnemooseus, posted 07-30-2004 11:14 PM | | Minnemooseus has not replied |
| Replies to this message: | | | Message 8 by Coragyps, posted 07-31-2004 11:02 AM | | bob_gray has not replied |
|
fnord
Inactive Member
|
pi-ing for the fnords
So, how DO you calculate Pi? Ask Rocket and his japanese supercomputer.
If there is one thing computers will never be able to do, it is to descend from apes -- Piet Grijs
| This message is a reply to: | | | Message 1 by Minnemooseus, posted 07-30-2004 11:14 PM | | Minnemooseus has not replied |
|
Coragyps
Member (Idle past 753 days) Posts: 5553 From: Snyder, Texas, USA Joined: 11-12-2002
|
|
|
Message 8 of 10 (129113)
07-31-2004 11:02 AM
|
Reply to: Message 6 by bob_gray
07-31-2004 12:29 AM
|
|
Re: using the arctan
Yeah! I knew it had minuses in it too! Maybe I should try it again, but with a calculator this time. Can you imagine being one of the poor sods they hired back in 1800 or so to calculate sines/logarithms longhand? To seven or eight decimals for every minute of arc from 0 to 90 degrees? With a quill pen?
| This message is a reply to: | | | Message 6 by bob_gray, posted 07-31-2004 12:29 AM | | bob_gray has not replied |
|
JustinC
Member (Idle past 4863 days) Posts: 624 From: Pittsburgh, PA, USA Joined: 07-21-2003
|
|
|
Message 9 of 10 (129140)
07-31-2004 2:42 PM
|
|
|
Pi Formulas -- from Wolfram MathWorld For ALL math questions, you can't go wrong with Mathworld. I referred to this site countless amounts of times. I can't believe how comprehensive it is and that it's free.
|
Minnemooseus
Member Posts: 3944 From: Duluth, Minnesota, U.S. (West end of Lake Superior) Joined: 11-11-2001 Member Rating: 10.0
|
|
|
Message 10 of 10 (129155)
07-31-2004 3:10 PM
|
Reply to: Message 9 by JustinC
07-31-2004 2:42 PM
|
|
Page has everything you need to know about Pi
Thank you. I'll have the admin mode close this topic. Moose
| This message is a reply to: | | | Message 9 by JustinC, posted 07-31-2004 2:42 PM | | JustinC has not replied |
|
™ Version 4.2