MATLAB PCode Warning on R2021a

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Danny Gho
Danny Gho on 10 Sep 2022
Answered: Walter Roberson on 10 Sep 2022
I am running MATLAB r2021a and I got this warning
Warning: P-file /home1/apps/matlab/2021a/toolbox/matlab/datatypes/isprop.p is older than MATLAB file /home1/apps/matlab/2021a/toolbox/matlab/datatypes/isprop.m.
/home1/apps/matlab/2021a/toolbox/matlab/datatypes/isprop.p may be obsolete and may need to be regenerated.
I understand that this mean that I need to regenerate the P-Code, but considering this is from matlab default toolbox, is there any way I can 'reset' my installation? Keep in mind that my matlab install is managed so I prefer something that can be done in the command line.
Thank you very much for your attention.

Accepted Answer

Jan on 10 Sep 2022
Edited: Jan on 10 Sep 2022
This can happen only, if somebody has edited the file isprop.m . Modifying Matlab's built-in functions is not useful and this cannot happen, if you work without admin privileges.
"I understand that this mean that I need to regenerate the P-Code." - no, don't do this. Usually the M-files of the toolbox functions contain the help section only. If you P-code them and overwrite the original P-file, the Matlab installation is damaged and need a repair e.g. by a re-installation.
The solution is to restore the original version of isprop.m from a backup or to re-install Matlab. Afterwards do not work with admin privilegs such that you cannot change the toolbox functions by accident.

More Answers (1)

Walter Roberson
Walter Roberson on 10 Sep 2022
I can tell from the path that you are using Linux. For Linux or MacOS, you can use the system utility touch utility to change the modification date associated with a file; see


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