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TauCeti.Algebra.Module.LocalizedModule.DirectSum

Localization of modules commutes with direct sums #

If each fᵢ : Mᵢ →ₗ[R] M'ᵢ is a localization of modules at a submonoid S of R, then so is the componentwise map ⨁ i, Mᵢ →ₗ[R] ⨁ i, M'ᵢ, for an arbitrary index type. This is the direct-sum counterpart of Mathlib's IsLocalizedModule.prodMap and IsLocalizedModule.pi.

instance IsLocalizedModule.directSum {R : Type u_1} [CommSemiring R] (S : Submonoid R) {ι : Type u_2} {M : ι → Type u_3} {M' : ι → Type u_4} [(i : ι) → AddCommMonoid (M i)] [(i : ι) → AddCommMonoid (M' i)] [(i : ι) → Module R (M i)] [(i : ι) → Module R (M' i)] (f : (i : ι) → M i →ₗ[R] M' i) [∀ (i : ι), IsLocalizedModule S (f i)] :

Localization of modules commutes with direct sums.