English
Defines an embedding mapDomainEmbedding : (α →₀ ℕ) ↪ (β →₀ ℕ) induced by an embedding f : α ↪ β.
Русский
Определяет вложение mapDomainEmbedding : (α →₀ ℕ) ↪ (β →₀ ℕ), индуцированное вложением f : α ↪ β.
LaTeX
$$$$ \mathrm{mapDomainEmbedding}\ {\alpha}\ {\beta}\ (f) : (\alpha \to_\mathbb{N} \!) \hookrightarrow (\beta \to_\mathbb{N} \!). $$$$
Lean4
/-- When `f` is an embedding we have an embedding `(α →₀ ℕ) ↪ (β →₀ ℕ)` given by `mapDomain`. -/
@[simps]
def mapDomainEmbedding {α β : Type*} (f : α ↪ β) : (α →₀ ℕ) ↪ β →₀ ℕ :=
⟨Finsupp.mapDomain f, Finsupp.mapDomain_injective f.injective⟩