MATLAB: Are MAT-file version 7.3 files not compressed by default in MATLAB 7.5 (R2007b)

-v7.3.mat file7.3bigcompressiondefaulthdf5largemat filesMATLABsavesavingslowversion

In the MATLAB documentation:
help –> MAT-File preferences (Under General Preferences for MATLAB)
help –> Saving and Loading MAT-Files –> Exporting Data to MAT-Files –> Data Compression
help –> save
The documentation on any of these features does not reflect or clarify whether MAT-files saved with version 7.3 are compressed or not.

Best Answer

This change has been incorporated into the documentation in Release 2009b (R2009b). For previous releases, read below for any additional information:
For MATLAB releases R2006b through R2007b MAT-files created with the SAVE command and the -v7.3 flag are not compressed.
It is possible to save variables in a compressed format for these releases by using the HDF5 file format.
For more information on HDF5 capabilities and MATLAB supported functions execute the following at the MATLAB command prompt:
DOC HDF5
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