English
There is an additive equivalence between the space of functions m → n → α and the space of matrices m × n with entries α, given by f ↦ of f.
Русский
Существует аддитивное эквивалентие между пространством функций m → n → α и пространством матриц m × n над α, задаваемое f ↦ of f.
LaTeX
$$$ (m \\to n \\to \\alpha) \\simeq_{+} \\mathrm{Matrix}(m,n,\\alpha) $$$
Lean4
/-- This is `Matrix.of` bundled as an additive equivalence. -/
def ofAddEquiv [Add α] : (m → n → α) ≃+ Matrix m n α
where
__ := of
map_add' _ _ := rfl