RE: MATLAB load/save changes

[Hall, Benjamin]

>> a = int8(5)/int8(3)

a =

    2

>> whos
  Name      Size                    Bytes  Class

  a         1x1                         1  int8 array
  ans       1x1                         1  int8 array

Grand total is 2 elements using 2 bytes

-----Original Message-----
From: John W. Eaton [mailto:address@hidden
Sent: Wednesday, September 01, 2004 10:31 AM
To: Quentin Spencer
Cc: address@hidden
Subject: MATLAB load/save changes


On 18-Aug-2004, Quentin Spencer <address@hidden> wrote:

| 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.

Thanks for the pointer.  I think Octave should handle the new file
format, but it is a low priority project for me right now.  If someone
else can contribute the code, that would be helpful.

Since you apparently have access to Matlab 7.0, can you tell us
whether

  int8(5) / int8(3)

returns int8(1) or int8(2)?

Thanks,

jwe