Note that X_test.mat needs to download manually from the given the links of google drive or baiduyun, due to its large size.
Google drive: https://drive.google.com/file/d/1JonHPynVZWCQ9EvZA-oXiFEPU-giIaYt/view?usp=sharing
Baiduyun: https://pan.baidu.com/s/1XRcKsckcYTqnD_zjOvWHoQ (access code: mrdf)