RE: Limit to length of lists?
- To: mathgroup at smc.vnet.net
- Subject: [mg34159] RE: [mg34140] Limit to length of lists?
- From: "David Park" <djmp at earthlink.net>
- Date: Tue, 7 May 2002 03:53:55 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Bob,
Unfortunately, you are not telling us exactly what you did. It looks like ss
did not get set to a list. If you feed ss to the kernel what do you get?
Anyway, on a Windows98 machine there is no problem in storing a list of that
size. Here I make a 40000 long list of your maximum number size.
ss = Table[2^32, {40000}];
Length[ss]
40000
ss[[10000]]
4294967296
MemoryInUse[]
2723504
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
> From: Bob Harris [mailto:nitlion at mindspring.com]
To: mathgroup at smc.vnet.net
>
> Howdy,
>
> I'm running into a problem where it seems like you just aren't allowed to
> assign a list of 40 thousand integers to a variable.
>
> I've narrowed the failure down to the steps shown below. Originally I was
> trying to import a large list, but when that failed I started
> trying to see
> just what worked and what didn't, and found that the problem has
> nothing to
> do with importing. The computation in the following will seem
> strange, but
> it creates a list that similar to one that I couldn't import. The
> computation is probably not related to the problem either.
>
> (1) In mathematica, I create a 40,000 entry list of numbers in the range
> 1..2^32/40000, and assign it to the variable tt.
>
> (2) Then I change the list so that each entry is the sum of the previous
> entries. This results in a sorted list where the numbers range
> from about 1
> to about 2^32.
>
> (3) Then I display that list, and cut and paste the whole list into an
> assignment to a variable named ss. ss has not been previously used. The
> asignment doesn't generate any complaints from Mathematica. The
> assingment
> looks like this:
> ss = {44672, ... , 2142701433};
> where the ... stands for 39,998 elements that I've left out of this mail
> message.
>
> (4) I then ask for Length[ss] and am told that it is zero. This is
> surprising, since the original list (which was created using Mathematica
> functions rather than just a big assignment) had the desired length (i.e.
> Length[tt] is 40000.
>
> (5) Attempts to index into ss also fail. For example, ss[[1]]
> gives me the
> messages
> Part::partd:
> Part specification ss[[1]] is longer than depth of object.
>
> (6) After quitting and relaunching Mathematica, I've tried doing
> steps 3, 4,
> and 5 by themselves. The failure is the same.
>
> Anyone have any idea what's goin on here? And how I can correct it? I've
> wandered so far away from what I was originally trying to do, I'm starting
> to get pretty frustrated. Is there some artificial limit imposed on the
> length of lists? Is there some way I can control it?
>
> I'm using Mathematica 4.0.1.0 on a G3 Mac running OS 9.0.4. I've
> got it set
> up to provide 20 MB for Mathematica and 30 MB for MathKernel.
>
> Thanks for any help,
> Bob H
>
>