The following Matlab project contains the source code and Matlab examples used for adds text labels a, b, c,... to subplots. . When publishing a paper, you need to label your subplots with "a)", "b)", etc in the upper left corner. This routine does it for you with no fuss or muss.
The source code and files included in this project are listed in the project files section, please make sure whether the listed source code meet your needs there.