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Mathlib.Algebra.Order.BigOperators.GroupWithZero.Multiset

Big operators on a multiset in ordered groups with zeros #

This file contains the results concerning the interaction of multiset big operators with ordered groups with zeros.

theorem Multiset.prod_nonneg {R : Type u_1} [CommMonoidWithZero R] [PartialOrder R] [ZeroLEOneClass R] [PosMulMono R] {s : Multiset R} (h : as, 0 a) :
0 s.prod
theorem Multiset.one_le_prod {R : Type u_1} [CommMonoidWithZero R] [PartialOrder R] [ZeroLEOneClass R] [PosMulMono R] {s : Multiset R} (h : as, 1 a) :
1 s.prod
theorem Multiset.prod_map_le_prod_map₀ {R : Type u_1} [CommMonoidWithZero R] [PartialOrder R] [ZeroLEOneClass R] [PosMulMono R] {ι : Type u_2} {s : Multiset ι} (f : ιR) (g : ιR) (h0 : is, 0 f i) (h : is, f i g i) :
(Multiset.map f s).prod (Multiset.map g s).prod
theorem Multiset.prod_pos {R : Type u_1} [CommMonoidWithZero R] [PartialOrder R] [ZeroLEOneClass R] [PosMulStrictMono R] [NeZero 1] {s : Multiset R} (h : as, 0 < a) :
0 < s.prod
theorem Multiset.prod_map_lt_prod_map {R : Type u_1} [CommMonoidWithZero R] [PartialOrder R] [ZeroLEOneClass R] [PosMulStrictMono R] [NeZero 1] {ι : Type u_2} {s : Multiset ι} (hs : s 0) (f : ιR) (g : ιR) (h0 : is, 0 < f i) (h : is, f i < g i) :
(Multiset.map f s).prod < (Multiset.map g s).prod