Y = SUBMREDUCE(X,R,C,F) treats the 2D matrix X as consisting of submatrices of RxC rows and columns, and returns a smaller matrix with one value derived from each of these submatrices.
That value is obtained by applying the function pointed to by F to a matrix where the all the submatrix values have been arranged in columns - i.e. the standard syntax for functions such as MIN() and SUM().
Example: if X = [1 2 3 4; 5 6 7 8] then SUBMREDUCE(X,2,2,@sum) = [14 22].
Dan Ellis (2020). SUBMREDUCE - submatrix reduce (https://www.mathworks.com/matlabcentral/fileexchange/16206-submreduce-submatrix-reduce), MATLAB Central File Exchange. Retrieved .