If neither X nor Y is a set, return the element-by-element comparison of X<Y.
If both X and Y are sets, check if X is a proper subset of Y.
- Parameters:
X (Constant) – A scalar/pair/vector/matrix/set.
Y (Constant) – A scalar/pair/vector/matrix/set. If X or Y is a pair/vector/matrix, the other
is a scalar or a pair/vector/matrix of the same size.
