Your Question:
I want to extract data for specific row and col for all the files i have (i.e., SM1,SM2,SM3,SM3).
For example, if you want to extract row 1 and column 2 from the variable in the mat file. Let assume that SM1 has variable sm1, SM2 has variable sm2,......
FileInfo=dir('SM*.mat');
for k= 1:length(FileInfo)
fileName=['sm' num2str(k)];
dataStruct=load(FileInfo(k).name);
dataStruct.(fileName)(1,2)
end