how to get mat file version, type(matfile) doesn't work

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Kangle Li 2020-4-15

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评论： Stephen23 2020-4-16

Hi, I tried "type(matfilename)" to get the mat file version, but this command will type out the contents of the mat file, not the version. So how to get the version of a mat file? Thanks in advance!

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Stephen23 2020-4-16

在 MATLAB Online 中打开

Did this behavior change? It worked for me on R2012b:

>> X = 1:3;
>> save('test.mat','X')
>> type('test.mat')
MATLAB 5.0 MAT-file, Platform: PCWIN, Created on: Thu Apr 16 11:08:37 2020

See also https://www.mathworks.com/matlabcentral/answers/111663-how-can-i-list-which-file-format-version-was-used-for-existing-mat-files

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Answer 1

Walter Roberson 2020-4-15

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https://ww2.mathworks.cn/matlabcentral/answers/518223-how-to-get-mat-file-version-type-matfile-doesn-t-work#answer_426289

fread() the first 16 bytes of the file.

'MATLAB 5.0 MAT-file' -> MATLAB 5.0 or 7.0 .mat file, saved with -v6 flag or with -v7 or (typically) with no -v flag

'MATLAB 7.3 MAT-file' -> MATLAB 7.3 .mat

no 'MATLAB' string at beginning but you know it is a .mat file -> .mat saved with -v4 flag

If you need to detect whether a file was stored with -v6 versus -v7 then there would be more work involved. The header does not differentiate between the two, but since -v6 does not support compression, it would be possible to look for clues such as the existence of compressed variables