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Mathlib.Data.NNRat.BigOperators

Casting lemmas for non-negative rational numbers involving sums and products #

theorem NNRat.cast_sum {α : Type u_1} {K : Type u_2} [DivisionSemiring K] [CharZero K] (s : Finset α) (f : αℚ≥0) :
(∑ as, f a) = as, (f a)
theorem NNRat.cast_prod {α : Type u_1} {K : Type u_2} [Semifield K] [CharZero K] (s : Finset α) (f : αℚ≥0) :
(∏ as, f a) = as, (f a)
theorem NNRat.toNNRat_sum_of_nonneg {α : Type u_1} {s : Finset α} {f : α} (hf : as, 0 f a) :
(∑ as, f a).toNNRat = as, (f a).toNNRat
theorem NNRat.toNNRat_prod_of_nonneg {α : Type u_1} {s : Finset α} {f : α} (hf : as, 0 f a) :
(∏ as, f a).toNNRat = as, (f a).toNNRat