Possibly: L is a scalar and x is a vector that is not the same length as size(T,1) so the calculated result does not fit into T(:,1)
Possibly: L is a scalar and x has 2 or more dimensions, so the shape of x is wrong to fit into the vector T(:,1)
Possibly: x and L are both vectors or arrays whose second dimensions happen to be equal; the result of the "/" matrix division operator will be size(x,1) by size(L,1), and that size does not fit into the vector T(:,1) . If x and L happen to be vectors of exactly the same length then probably the ./ operator should have been used instead of the / operator
