--- a
+++ b/Xsys_MT_cal.m
@@ -0,0 +1,14 @@
+function [Xsys_MT] = Xsys_MT_cal(Xs, ys)
+%Calculate Xty for each task and arrange them according to both the orders
+%of the features and the tasks
+
+
+Xsys_MT = zeros(size(Xs{1},2)*length(Xs),1);
+idx_row = (0:size(Xs{1},2)-1)*length(Xs)+1;
+for i = 1 : length(Xs)
+    Xty = (Xs{i})'*(ys{i});
+    Xsys_MT(idx_row,1) = Xty;
+    idx_row = idx_row + 1;
+end
+
+end
\ No newline at end of file