Reading matlab structures in mat files does not seem supported at this point.
Version 7 3 mat file.
Matlab s matfile objects enable users to access and change variables stored in version 7 3 mat files without loading the entire variable into memory.
Endian indicator contains the two characters m and i written to the mat file in this order as a 16 bit value.
Up through version 7 mat files individual variables are limited to 2gb in size.
Beginning at release 7 3 of matlab mat files are actually saved using the hdf5 format by default except if you use the vx flag at save time see help save in matlab.
To identify or change the default mat file version access the mat files preferences.
Matlab 7 1 r14sp3 1 5 0 september 1 2005 first 64 bit version available for windows xp 64 bit matlab 7 2 r2006a 15 1 5 0 2006 march 1 2006 matlab 7 3 r2006b 16 1 5 0 september 1 2006 hdf5 based mat file support matlab 7 4 r2007a 17 1 5 0 07 2007 march 1 2007.
March 7 2005 support for memory mapped files.
There are third opensource implementations of v7 3 mat file available so porting this to octave shouldn t require redo this from scratch.
The only exception to this is when you create new mat files using the matfile function.
In this case the default mat file version is 7 3.
Version 7 3 removes this restriction allowing variables to be arbitrarily large.
These files can be read in python using for instance the pytables or h5py package.
The only exception to this is when you create new mat files using the matfile function.
By default all save operations create version 7 mat files.
If you look at the help of save v7 3 means version 7 0 features plus support for data items greater than or equal to 2gb on 64 bit systems which should be in your advantage.
If when read from the mat file as a 16 bit value the characters appear in reversed order im rather than mi it indicates that the program reading the mat file must.
Also given that the v7 3 mat file is matlab s default and the only one option in matlab that can cope with variables larger than 2gb which is not that much nowadays we some octave users feel that it would be nice if developers could prioritize this.
Your matlab is r2010a which should be later than v7 3.
Version when creating a mat file set this field to0x0100.
In this case the default mat file version is 7 3.
The save variables to version 7 3 mat file example on that page shows the exact syntax.