# Re: value of pi and 22/7

Discussion in 'Python' started by Kee Nethery, Mar 17, 2011.

1. ### Kee NetheryGuest

My favorite approximation is: 355/113 (visualize 113355 split into two 113 355 and then do the division). The first 6 decimal places are the same.

3.141592920353982 = 355/113
vs
3.1415926535897931

Kee Nethery

Kee Nethery, Mar 17, 2011

2. ### peterGuest

On Mar 17, 5:22 pm, Kee Nethery <> wrote:
> My favorite approximation is: 355/113  (visualize 113355 split into two113 355 and then do the division). The first 6 decimal places are the same..
>
> 3.141592920353982 = 355/113
> vs
> 3.1415926535897931
>
> Kee Nethery

Or (more for fun than any practical application) try (2143/22)^(1/4) =
3.14159265268.

Other approximations I have seen are root(10) and 3.142. This last
was especially popular at school, which for me was sufficiently long
ago to have used four figure log tables.

The Old Testament (1 Kings 7,23) says ... "And he made a molten sea,
ten cubits from the one brim to the other: it was round all about, and
his height was five cubits: and a line of thirty cubits did compass it
round about. ". So pi=3. End Of.

peter, Mar 18, 2011

3. ### Neil CeruttiGuest

On 2011-03-18, peter <> wrote:
> The Old Testament (1 Kings 7,23) says ... "And he made a molten
> sea, ten cubits from the one brim to the other: it was round
> all about, and his height was five cubits: and a line of thirty
> cubits did compass it round about. ". So pi=3. End Of.

RIIIIIIght. What's a cubit?

--
Neil Cerutti

Neil Cerutti, Mar 18, 2011
4. ### Stefan BehnelGuest

Neil Cerutti, 18.03.2011 13:17:
> On 2011-03-18, peter<> wrote:
>> The Old Testament (1 Kings 7,23) says ... "And he made a molten
>> sea, ten cubits from the one brim to the other: it was round
>> all about, and his height was five cubits: and a line of thirty
>> cubits did compass it round about. ". So pi=3. End Of.

>
> RIIIIIIght. What's a cubit?

http://en.wikipedia.org/wiki/Cubit

I think that particular author of that particular part of the bible just
used it to make the text appear older than it was at the time.

Stefan

Stefan Behnel, Mar 18, 2011
5. ### D'Arcy J.M. CainGuest

D'Arcy J.M. Cain, Mar 18, 2011
6. ### Neil CeruttiGuest

On 2011-03-18, Stefan Behnel <> wrote:
> Neil Cerutti, 18.03.2011 13:17:
>> On 2011-03-18, peter<> wrote:
>>> The Old Testament (1 Kings 7,23) says ... "And he made a molten
>>> sea, ten cubits from the one brim to the other: it was round
>>> all about, and his height was five cubits: and a line of thirty
>>> cubits did compass it round about. ". So pi=3. End Of.

>>
>> RIIIIIIght. What's a cubit?

>
> http://en.wikipedia.org/wiki/Cubit
>
> I think that particular author of that particular part of the
> bible just used it to make the text appear older than it was at
> the time.

--
Neil Cerutti

Neil Cerutti, Mar 18, 2011
7. ### Aage AndersenGuest

"peter"
Kee Nethery > My favorite approximation is: 355/113 (visualize 113355 split
into two 113 355 and then do the division). The first 6 decimal places are
the same.
>
> 3.141592920353982 = 355/113
> vs
> 3.1415926535897931
>
> Kee Nethery

Or (more for fun than any practical application) try (2143/22)^(1/4) =
3.14159265268.

Other approximations I have seen are root(10) and 3.142. This last
was especially popular at school, which for me was sufficiently long
ago to have used four figure log tables.

The Old Testament (1 Kings 7,23) says ... "And he made a molten sea,
ten cubits from the one brim to the other: it was round all about, and
his height was five cubits: and a line of thirty cubits did compass it
round about. ". So pi=3. End Of.
-------------------------------------------------------------------

3 is the best integer approximation to pi. So the bibel is right.

Aage

Aage Andersen, Mar 18, 2011
8. ### Stefan BehnelGuest

Sherm Pendley, 18.03.2011 14:46:
> Stefan Behnel writes:
>
>> Neil Cerutti, 18.03.2011 13:17:
>>> On 2011-03-18, peter<> wrote:
>>>> The Old Testament (1 Kings 7,23) says ... "And he made a molten
>>>> sea, ten cubits from the one brim to the other: it was round
>>>> all about, and his height was five cubits: and a line of thirty
>>>> cubits did compass it round about. ". So pi=3. End Of.
>>>
>>> RIIIIIIght. What's a cubit?

>>
>> http://en.wikipedia.org/wiki/Cubit
>>
>> I think that particular author of that particular part of the bible
>> just used it to make the text appear older than it was at the time.

>
> Sigh. Doesn't *anyone* know Cosby any more? Kids today, no appreciation
> for the classics. :-(

And what about Heinz Erhardt? *That's* a classic.

Stefan

Stefan Behnel, Mar 18, 2011
9. ### Grant EdwardsGuest

On 2011-03-18, peter <> wrote:

> The Old Testament (1 Kings 7,23) says ... "And he made a molten sea,
> ten cubits from the one brim to the other: it was round all about, and
> his height was five cubits: and a line of thirty cubits did compass it
> round about. ". So pi=3. End Of.

There's nothing wrong with that value. The measurements were given
with one significant digit, so the ratio of the two measurements
should only have one significant digit.

--
Grant Edwards grant.b.edwards Yow! It's some people
at inside the wall! This is
gmail.com better than mopping!

Grant Edwards, Mar 18, 2011
10. ### Kee NetheryGuest

On Mar 18, 2011, at 5:17 AM, Neil Cerutti wrote:

> On 2011-03-18, peter <> wrote:
>> The Old Testament (1 Kings 7,23) says ... "And he made a molten
>> sea, ten cubits from the one brim to the other: it was round
>> all about, and his height was five cubits: and a line of thirty
>> cubits did compass it round about. ". So pi=3. End Of.

>
> RIIIIIIght. What's a cubit?

I use cubits all the time. The distance from my elbow to my finger tips equals one cubit. When you don't have a proper measuring tape, it can be pretty accurate for comparing two measurements.

Kee Nethery

Kee Nethery, Mar 18, 2011
11. ### John GordonGuest

In <> Neil Cerutti <> writes:

> RIIIIIIght. What's a cubit?

How long can you tread water?

--
John Gordon A is for Amy, who fell down the stairs
B is for Basil, assaulted by bears
-- Edward Gorey, "The Gashlycrumb Tinies"

John Gordon, Mar 18, 2011

On Fri, 2011-03-18 at 14:16 +0000, Grant Edwards wrote:
> On 2011-03-18, peter <> wrote:
> > The Old Testament (1 Kings 7,23) says ... "And he made a molten sea,
> > ten cubits from the one brim to the other: it was round all about, and
> > his height was five cubits: and a line of thirty cubits did compass it
> > round about. ". So pi=3. End Of.

> There's nothing wrong with that value. The measurements were given
> with one significant digit, so the ratio of the two measurements
> should only have one significant digit.

I've worked in landscaping and [low-scale] agriculture - pi as 3 is used
all the time. It is easy to compute in your head and close enough.

Adam Tauno Williams, Mar 18, 2011
13. ### Dennis Lee BieberGuest

On Fri, 18 Mar 2011 14:05:07 +0100, "Aage Andersen"
<aaan(REMOVE)@email.dk> declaimed the following in
gmane.comp.python.general:

> Other approximations I have seen are root(10) and 3.142. This last
> was especially popular at school, which for me was sufficiently long
> ago to have used four figure log tables.
>

Strange... Somewhere around 12 grade I finally memorized it as

3.141592654 where the 4 is a 36 rounded

As you can probably guess -- from a scientific calculator with a hidden
guard digit <G>
--
Wulfraed Dennis Lee Bieber AF6VN
HTTP://wlfraed.home.netcom.com/

Dennis Lee Bieber, Mar 19, 2011
14. ### Steven D'ApranoGuest

On Fri, 18 Mar 2011 07:22:43 -0700, Kee Nethery wrote:

> On Mar 18, 2011, at 5:17 AM, Neil Cerutti wrote:
>
>> On 2011-03-18, peter <> wrote:
>>> The Old Testament (1 Kings 7,23) says ... "And he made a molten sea,
>>> ten cubits from the one brim to the other: it was round all about, and
>>> his height was five cubits: and a line of thirty cubits did compass it
>>> round about. ". So pi=3. End Of.

>>
>> RIIIIIIght. What's a cubit?

>
> I use cubits all the time. The distance from my elbow to my finger tips
> equals one cubit. When you don't have a proper measuring tape, it can be
> pretty accurate for comparing two measurements.

"Measure with micrometer, mark with chalk, cut with axe."

Just wait until you tell your apprentice to go fetch a piece of wood
three cubits long... damn kids with their short/long arms...

--
Steven

Steven D'Aprano, Mar 19, 2011