MATLAB load/save changes

[Quentin Spencer]

I'm not sure whether to report this as a bug or just as an FYI to the 
maintainers, so I'm posting it to both. Back in March, John sent out a 
list of new features listed as new in the then-upcoming MATLAB 7. I've 
just run into a load/save incompatibility that wasn't in that list. 
Trying to load a file saved in MATLAB 7, I got an error. In the 
documentation for MATLAB's save function, I found the following:

   By default, MAT-files created with SAVE are compressed and char 
arrays are
   encoded using Unicode. These MAT-files cannot be loaded into versions of
   MATLAB prior to MATLAB 7.0. The -V6 option disables these features and
   allows saved MAT-files to load into older versions of MATLAB. To disable
   these features by default, modify the settings in the General->MAT-Files
   preferences panel, accessible via the File->Preferences menu item. With
   compression enabled, saving data that does not compress well takes
   longer. In this case, the -V6 option may be preferable.

The file in question didn't have any char arrays, so I suspect it was 
the compression that tripped it up. I looked briefly at the file format 
document on their web site:
   
http://www.mathworks.com/access/helpdesk/help/pdf_doc/matlab/matfile_format.pdf
It looks like it's all documented--they are using gzip compression on 
each variable.

-Quentin