English
BlockDiagonal defines a ring homomorphism from a family of matrices to a block matrix, respecting addition and multiplication.
Русский
BlockDiagonal образует кольцевой гомоморфизм от семейства матриц к блочной матрице, сохраняющий сложение и умножение.
LaTeX
$$$\operatorname{blockDiagonalRingHom} : (o \to Matrix m m α) \to_* Matrix (m \times o) (m \times o) α$$$
Lean4
@[simp]
theorem blockDiagonal_smul {R : Type*} [Zero α] [SMulZeroClass R α] (x : R) (M : o → Matrix m n α) :
blockDiagonal (x • M) = x • blockDiagonal M := by
ext
simp only [blockDiagonal_apply, Pi.smul_apply, smul_apply]
split_ifs <;> simp