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Re: Out of Memory Problem (beginner)

  • To: mathgroup at smc.vnet.net
  • Subject: [mg44463] Re: Out of Memory Problem (beginner)
  • From: "Dana DeLouis" <delouis at bellsouth.net>
  • Date: Mon, 10 Nov 2003 19:55:48 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

> A = Table[i,{i,1,6000},{j,1,7000}]

Just a point.  I noticed on your example that you do not have a trailing
";"  to hide the final output of the Table.
Most likely, you are calculating the Array "A", but the program is
running out of memory trying to display the Array.
I know!   I uh.did the same thing.  I had the same results as you.  :>)

It's a large array.  Even as a Packed Array, it's still large.

v = Table[i, {i, 1, 6000}, {j, 1, 7000}]; 

 {PackedArrayQ[v], ByteCount[v]}
 {True, 168,000,060}

Maybe you could dump the solution to a file on the hard drive?

size = Dimensions[A][[1]]
6000

Table[
A[[r,All]] . A[[c,All]] >>> "C:\\Temp.m",
 {r, size}, {c, size}
];


= = = = 
As a side note, I am not very happy with the way Mathematica 5 handels
its memory.  It is almost always crashing my system.  This never
happened before in earlier versions.  I've never gotton a memory problem
before until ver. 5.
The program often sends my hard drive into a continuous run that won't
quit.  After about 5+ minutes of the hard drive running (After I somehow
get the kernel to quit) I get concerned about my computer.
The computer is pretty much locked up after this, so I have to reboot.
I think the program has a serious memory problem.
( I have 256k memory, 40G hard drive, and have my $HistoryLength set
low.)

-- 
Dana DeLouis
Windows XP
Mathematica 5.0 for Windows 
delouis at bellsouth.net


"Cedric" <cedric at ddd.co.jp> wrote in message
news:<bo7pdn$am2$1 at smc.vnet.net>...
> Hello,
> 
> I have a matrix of 6000 x 7000.
> A = Table[i,{i,1,6000},{j,1,7000}]
> I'd like to calculate A.Transpose[A].
> But it appears "Out of Memory" problem after
> trying to calculate for a long time.
> 
> Does anybody know how i can olve the above problem?
> 
> Thank you in advance,
> 
> Cedric



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