In symbol A h, A is a complex matrix, and A h stands for * * * yoke transposition of A (take * * yoke for each element and transpose the whole matrix).

V ⊥ In this notation, V represents a linear (subspace) and V ⊥ represents the orthogonal complement space of V.

Generally speaking, the notation of ⊥ is rarely used in matrices, and if it is used, it will be defined, because it is not a very common notation. )