Re: Loading a 318 MB matrix into Octave 32 bit

[c.]

On 29 Jul 2013, at 02:21, Elliot Gorokhovsky <address@hidden> wrote:

> I am running 32 bit octave on a 64 bit system (I would really like to keep it 
> that way if possible) and I have a .mat with a double matrix size 5492743 by 
> 3. Octave says it takes 131,825,832 bytes. When I run the following script 
> (with num=140000) I get, immediately[, error: memory exhausted or requested 
> size too large for range of Octave's index type -- trying to return to prompt.
> 
> data = [data,zeros(length(data),num*3)];
> for i = 1:length(data)-num
> data(i,:)=[data(i,1:3),vec(data((i+1):(i+num),1:3)')'];
> disp(i)
> end
> data = data(1:length(data)-num,:);
> 
> Can I fix this without recompiling? If I have to recompile, how do I do it?
> 
> Thanks, 
> Elliot Gorokhovsky


Hi, 
This sounds strange to me, your matrix size seems to be below 
the limit that can be indexed with 32 bit integers
which, if I am not mistaken, is 

2^32 / 2 = 2.1475e+09 > 131,825,832

indeed whith my version of Octave (3.7.5 compiled without support for 64 bit 
indexing) 
I can save and load a matrix that size with no problem:

>> a = randn (5492743, 3);
>> save -binary -z pippo.octbin.gz a
>> clear all
>> load pippo.octbin.gz
>> whos a
Variables in the current scope:

   Attr Name         Size                     Bytes  Class
   ==== ====         ====                     =====  ===== 
        a      5492743x3                  131825832  double

Total is 16478229 elements using 131825832 bytes

>> ls -lh pippo.octbin.gz 
-rw-r--r--  1 carlo  wheel   121M 29 Jul 08:38 pippo.octbin.gz


so I wonder where your problem comes from. How did you install your version of 
Octave?

c.