Estimating PI without a calculator

Estimating PI without a calculator - Printable Version

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Estimating PI without a calculator - Don Williams - 04-15-2014 06:49 PM

It seems we don't need RPN.

https://medium.com/the-physics-arxiv-blog/c1eb776193ef

Just grab your pump action shotgun and use the Monte Carlo method.

RE: Estimating PI without a calculator - Dave Britten - 04-15-2014 07:57 PM

Worked great for exams where calculators weren't permitted. I nearly got expelled/arrested trying to do e^x, though.

RE: Estimating PI without a calculator - everettr - 04-15-2014 09:15 PM

I hear these fellows are working on a follow-up article describing their results for a variation on an old classic. The preliminary title is, "Buffon's Big Bore Blaster".

RE: Estimating PI without a calculator - davetheguru - 04-16-2014 01:07 AM

Or if you just have a 4 function simple one...
An reasonably accurate estimate can be done by taking the sequence:
1 1 3 3 5 5
and putting the old division box /---- in the middle (sorry for the poor drawing but this way helps remember to process for some) so that you have:
____
113 / 355 or rather,

355
----
113

to get something like:
3.14159292035 (on my HP50)

RE: Estimating PI without a calculator - Matt Agajanian - 04-16-2014 02:41 AM

(04-15-2014 06:49 PM)Don Williams Wrote: It seems we don't need RPN.

https://medium.com/the-physics-arxiv-blog/c1eb776193ef

Just grab your pump action shotgun and use the Monte Carlo method.

Quite a drastic methodology, wouldn't you say.

RE: Estimating PI without a calculator - Thomas Klemm - 04-16-2014 02:41 AM

(04-15-2014 06:49 PM)Don Williams Wrote: It seems we don't need RPN.

Who said we can't do it with RPN?

Code:

00 { 8 Byte Prgm }

01 2

02 STO* ST Z

03 +

04 SQRT

05 STO/ ST Y

06 END

Start with:
2 ENTER
0

Then just keep hitting the [R/S] key.

Cheers
Thomas

RE: Estimating PI without a calculator - Thomas Klemm - 04-16-2014 02:46 AM

(04-16-2014 01:07 AM)davetheguru Wrote: An reasonably accurate estimate can be done by taking the sequence:
1 1 3 3 5 5

For even better accuracy I tried:
1 1 3 3 5 5 7 7

Was disappointed. Huh

RE: Estimating PI without a calculator - Dave Frederickson - 04-16-2014 03:50 AM

An estimate for pi without a calculator. Using my Memory Recall function I get 3.14, or just 3 if it's been a rough week.

RE: Estimating PI without a calculator - walter b - 04-16-2014 04:30 AM

(04-15-2014 06:49 PM)Don Williams Wrote: Just grab your pump action shotgun and use the Monte Carlo method.

Quite appropriate in an area where shotguns are more common than RPN calculators. HP, for the sake of the nation, counteract!

RE: Estimating PI without a calculator - Katie Wasserman - 04-16-2014 04:59 PM

Quote:Then just keep hitting the [R/S] key.

No need to do that. Here's an old thread about Viete's method and a really small, self stopping program.

RE: Estimating PI without a calculator - JimP - 04-17-2014 12:18 AM

(04-16-2014 02:41 AM)Thomas Klemm Wrote:
(04-15-2014 06:49 PM)Don Williams Wrote: It seems we don't need RPN.

Who said we can't do it with RPN?

Code:

00 { 8 Byte Prgm } 01 2 02 STO* ST Z 03 + 04 SQRT 05 STO/ ST Y 06 END

Start with:
2 ENTER
0

Then just keep hitting the [R/S] key.

Cheers
Thomas

I'm struggling with the concept of hitting an R/S key (or any other key, for that matter) when the topic is about estimating pi WITHOUT a calculator. Just to be precise, I took my Castell-Novo Duplex 2/83N, aligned the 22 on the C scale with 7 on the D scale, moved the cursor over to the 10 on the D scale, and bold as brass on the C scale was the symbol for pi. So there...

RE: Estimating PI without a calculator - Thomas Klemm - 04-17-2014 05:15 AM

(04-17-2014 12:18 AM)JimP Wrote: I took my Castell-Novo Duplex 2/83N

You could drop it multiple times on a cross-walk and count how often it's crossing lines:

RE: Estimating PI without a calculator - colinh - 04-19-2014 09:29 PM

(04-17-2014 05:15 AM)Thomas Klemm Wrote:
(04-17-2014 12:18 AM)JimP Wrote: I took my Castell-Novo Duplex 2/83N

You could drop it multiple times on a cross-walk and count how often it's crossing lines:

That would work with the shotgun too, when you're out of ammo, wouldn't it?