I have a mat file (saved from within MAtlab R2012b) loading issue with the newest version of Octave:
GNU Octave, version 3.6.4
octave:1> load thermo
error: load: invalid element type = 15
error: load: trouble reading binary file 'thermo'
However, this works fine in an older version.
GNU Octave, version 3.4.3
octave:1> load thermo.mat
octave:2> whos
Variables in the current scope:
Attr Name Size Bytes Class
==== ==== ==== ===== =====
Temp1 15x1 120 double
Temp2 15x1 120 double
Temp3 15x1 120 double
ans 1x39 363 cell
Total is 84 elements using 723 bytes