Re: error loading Matlab 5.0 binary : invalid element type

[David Bateman]

Marco Scoffier wrote:
> Hello all,
> 
> I have had generally good luck opening MatLab files with octave, however I
> now have a whole dataset which is giving me the same error:
> 
> octave:3> load annotation_0001.mat 
> error: load: invalid element type
> error: load: trouble reading binary file `annotation_0001.mat'
> octave:3> load -mat-binary annotation_0001.mat 
> error: load: invalid element type
> error: load: trouble reading binary file `annotation_0001.mat'
> 
> The data comes from the Annotations for the Caltech 101 data used for
> Computer Vision: http://www.vision.caltech.edu/feifeili/Datasets.htm
> 
> I can post a single example of a file if it helps to track down the source
> of the error.  (not sure about attaching files to this list). The
> beginning of the first line in file is:
> 
> MATLAB 5.0 MAT-file, Platform: PCWIN, Created on: Tue Nov 09 11:34:14 2004 
> 
> Identical to files I have opened successfully in the past.
> 
> Thanks for any pointers,
> 

I suspect the problem is exactly what it says. That there is an invalid
element type "for octave". That is octave doesn't implement certain of
the matlab types in matlab files. These include anything of the
mxOBJECT_CLASS which is used to store things like inline functions, and
graphics handles, or of the mxFUNCTION_CLASS. Note similar functionality
is implemented in the octave file type though. Another thing that might
stop a matlab file being loaded is if you use a complex integer type
like mxINT32_CLASS as octave implements only real integer types...

Regards
David