Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » Software » comp.soft-sys.math.mathematica

Topic: memory use
Replies: 2   Last Post: Sep 20, 1996 12:51 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
Harald Berndt

Posts: 6
Registered: 12/7/04
Re: memory use
Posted: Sep 20, 1996 12:48 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

Russell Towle wrote:
>
> ... so I thought that writing it to a file might be a good device.
>
> I use the syntax, (biglist >> "filename"), but to my surprise, the kernel
> requires tons of memory to execute this, even though the list "biglist" is
> already evaluated, and every element in it already resides in memory.
>
> By allocating 40 MB of memory to the kernel, I was able to write the list
> to a file. The file size itself was only 3MB. Why does MMA need 16


Yeah, well ... I ran into that problem quite often myself. I think the
problem is that using

biglist >> "filename"

one makes Mathematica convert all the numbers in the list from Mma's
internal representation to strings (in particular, each real is
written as an 18+ digit string), then write those strings to disk.
Very memory-demanding! A workaround might be to write your own binary
read and write routines (or just use those available, if that's
sufficient ... haven't looked at that in detail lately).

--
______________________________________________________________________
Harald Berndt, Ph.D. Research Specialist,
Consultant

Phone: 510-652-5974 FAX: 510-215-4299
______________________________________________________________________
"I yam what I yam"...................................Popeye the sailor
(Kryten:............"I thought that was Descartes!"..................)
(Lister:............"So did I. mon, so did I!".......................)









Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.