Re: memory use
- To: mathgroup at smc.vnet.net
- Subject: [mg4819] Re: memory use
- From: Harald Berndt <hberndt9 at mail.idt.net>
- Date: Fri, 20 Sep 1996 01:12:40 -0400
- Organization: IDT Corporation
- Sender: owner-wri-mathgroup at wolfram.com
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
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