Many digits of pi again

[Benoit Maag]

This is in reference to the article by Katie listing several programs for various machines to calculate many digits of pi in record time, posted Oct 17, 2008

http://www.hpmuseum.org/cgi-sys/cgiwrap/...i?read=899

Some programs manage 6 digits per memory, some 7 or 8. I suspect the choice is based on a combination of internal precision of calculation and the number of terms calculated. Is there a thread describing how to select the number of digits per memory? Or can someone clarify that? (Katie?)

Thank you - sorry if this is a repeat

Benoit

[Katie Wasserman]

(01-27-2014 06:44 AM)Benoit Maag Wrote:  Some programs manage 6 digits per memory, some 7 or 8. I suspect the choice is based on a combination of internal precision of calculation and the number of terms calculated. Is there a thread describing how to select the number of digits per memory? Or can someone clarify that? (Katie?)

Yes, you've got that exactly right.

The argument gos something like this:

I have a 10-digit calculator so I can fit 8 digits into each memory register allowing for multiplication/division of up to 2 digits. So now I can calculate up to 1000 digits. But at XXX digits I need 3 digits in my multiplication/division so I can only use 7 digits per register.

You can write a simple formula for this but there are idiosyncrasies of each calculator that need to be taken into consideration and certain programing tricks allow for more (or less) precision, etc.. It's not easy to figure out the maximum number of digits unless you error on the side of caution or do it experimentally.

The 16C is a fun calculator to play this game on since it gives you such nice control over the word size.

[Frozen North]

There is the program pi available on Linux systems which calculates π to a specified number of decimal digits.

On a Linux machine connected to the Internet, at a terminal command line enter:

Code:

sudo apt-get install pi

The man page for pi gives the usage details.

Example:

Code:

$ pi 64
3.141592653589793238462643383279502884197169399375105820974944592

Before installing the program, you might want to update your system.

Code:

sudo apt-get update
sudo apt-get upgrade

The above could take a while.

[davetheguru]

isn't it pointless to calculate it when it exists other places out more places than you can hope for on a calculator?
http://www.piday.org/million/

[Massimo Gnerucci]

(03-23-2014 12:20 AM)davetheguru Wrote:  isn't it pointless to calculate it when it exists other places out more places than you can hope for on a calculator?
http://www.piday.org/million/

Oh well... almost everything can be made faster and better than on a calculator.
Isn't it?

[Dieter]

(03-23-2014 12:11 AM)Geir Isene Wrote:  Wow - way cool. Didn't know about the "pi" program.

With internet access, the only program required to get thousands of digits of pi is a web browser. ;-)

(03-23-2014 12:11 AM)Geir Isene Wrote:  The requirement for membership was to recite pi to 52 decimals and e to 34 decimals.

52 and 34? Why that?

(03-23-2014 12:11 AM)Geir Isene Wrote:  We got to around 350 decimals before we found other fun stuff to do.

Ah, those were the days, when memorizing pi was "fun stuff". :-))

(03-23-2014 12:11 AM)Geir Isene Wrote:  We never got to be more than three members, though :-)

Fun for a selected audience, that is. ;-)

Dieter

[d b]

the final word on this subject: http://www.smbc-comics.com/index.php?id=3639

[rprosperi]

(02-12-2015 07:06 PM)Den Belillo (Martinez Ca.) Wrote:  the final word on this subject: http://www.smbc-comics.com/index.php?id=3639

Thanks Den! I know just the people to send this too... we too were a group of guys that tried to out-memorize each other with digits of PI. One of them brought in an article once that showed it could be calculated as an infinite series, and we just pooh-poohed him. He will really enjoy this today.