Re: Save produces large files

[Quentin Spencer]

Søren Hauberg wrote:

> I need to save some large (approx. 200x10000) matrices. Is there a
> recommended data format for this. At school I'm short on disk space
> (stupid sysadmins :-) ) so I'd rather not spend more space then I'd
> have to.
> Using save -binary two of these matrices consume 20Mb, which also
> means they are slow to load via NFS.

Well, since octave stores numbers as double precision by default, that's
8 bytes per matrix element, and 200*10000*8 = 16000000 bytes per matrix
(assuming the matrix is real). I guess the important question is do you
need double precision? If the data can be stored using limited precision
(32 bit float or integer) then you can cut the size in half. If it could
be stored as 16-bit integer, then you could get the size down to 4 MB
per matrix, which is still large, but a step in the right direction.

-Quentin



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------