Re: Printing digits of Pi
- To: mathgroup at smc.vnet.net
- Subject: [mg46710] Re: Printing digits of Pi
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Tue, 2 Mar 2004 19:10:08 -0500 (EST)
- Organization: The University of Western Australia
- References: <c215vo$8gv$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
In article <c215vo$8gv$1 at smc.vnet.net>, cmduncan at mines.edu wrote: > Hello! I am having an issue with printing the digits of Pi that mathematica > calculates. I can get a screen print of the digits to about 20 million but > interested in ~32 million digits. You really are printing out 20 million digits? Why are you doing this? I mean, why not compute and save the digits and then you can work with any block of digits you want. Also, I wonder what is the application. You are probably aware of http://mathworld.wolfram.com/PiFormulas.html and http://www.sciencenews.org/pages/sn_arc98/2_28_98/mathland.htm > Using the N command, I can get Mathematica > to determine the ~32 million digits but not print them to the screen. I get > a message "Out of Memory". Running at 4GB of physical memory should be > sufficient? Right? There are (sometimes very large) overheads in formatting output. However, exceeding 4GB seems a little extreme. Using MemoryInUse (which gives the number of bytes currently being used to store all data in the curren session -- which does not tell the full story) we see that about 1 extra MByte is required to print out 1 million digits. mem = MemoryInUse[]; N[Pi, 10^6] < output omitted > MemoryInUse[] - mem 3579624 mem = MemoryInUse[]; N[Pi, 10^6]; MemoryInUse[] - mem 2579496 Depending on your operating system, there are (external) ways to see how much (total) memory Mathematica is using for computation, formatting, and output. > Is there a way for Mathematica to create an output file > to print the digits for a given amount (i.e. 10 million versus 100 million)? You can easily create output files: lookup Put, Write, and Export. You can also work within Mathematica. For example, here is a way to examine the 1000 digits starting at the millionth digit after the decimal point: pi = RealDigits[N[Pi, 32 10^6]]; pi[[1,Range[10^6+1,10^6+10^3]]] > Is there a way to allow Mathematica to utilitize more physical memory than > defaulted? Surely this is an operating system issue, not a Mathematica issue? Cheers, Paul -- Paul Abbott Phone: +61 8 9380 2734 School of Physics, M013 Fax: +61 8 9380 1014 The University of Western Australia (CRICOS Provider No 00126G) 35 Stirling Highway Crawley WA 6009 mailto:paul at physics.uwa.edu.au AUSTRALIA http://physics.uwa.edu.au/~paul