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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: breaking up a large matrix before loading into matlab
Date: Fri, 3 Jul 2009 06:48:01 +0000 (UTC)
Organization: FOGALE nanotech
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dpb <none@non.net> wrote in message <h2jh0c$edq$2@news.eternal-september.org>...
> gary12345 wrote:
> > Does anybody know how I can load parts of a matrix into matlab
> > instead of all at once? because matlab won't allow me to load it all
> > at once because the matrix is too big. Thanks.
> 
> If it's a binary or text file see the doc for the appropriate input 
> function--they have optional arguments to include number of elements to 
> read.
> 
> If some other ML system did a SAVE to a .MAT file, there I'm not sure 
> outside a mex file or other hack to get at the data around the structure 
> of the file that there is...

I have not seen he internal format of MAT file documented anywhere. Not sure how to hack it.

Best recommendation is to find a computer with Matlab and large RAM to break down the file.

Few possible attempts: Try first to load the file after CLEAR ALL command. It is possible that the SAVE command is carried out on the same computer with large data-sharing variables. LOAD - since unshared them - thus will be unable to read it on the very same computer. In this case load individual variables separately - interleaved with clear all - might work. If it doesn't pass, then you are screwed.

Bruno