Ordered monoid and group homomorphisms #
This file defines morphisms between (additive) ordered monoids.
Types of morphisms #
OrderAddMonoidHom
: Ordered additive monoid homomorphisms.OrderMonoidHom
: Ordered monoid homomorphisms.OrderMonoidWithZeroHom
: Ordered monoid with zero homomorphisms.OrderAddMonoidIso
: Ordered additive monoid isomorphisms.OrderMonoidIso
: Ordered monoid isomorphisms.
Notation #
→+o
: Bundled ordered additive monoid homs. Also use for additive group homs.→*o
: Bundled ordered monoid homs. Also use for group homs.→*₀o
: Bundled ordered monoid with zero homs. Also use for group with zero homs.≃+o
: Bundled ordered additive monoid isos. Also use for additive group isos.≃*o
: Bundled ordered monoid isos. Also use for group isos.≃*₀o
: Bundled ordered monoid with zero isos. Also use for group with zero isos.
Implementation notes #
There's a coercion from bundled homs to fun, and the canonical notation is to use the bundled hom as a function via this coercion.
There is no OrderGroupHom
-- the idea is that OrderMonoidHom
is used.
The constructor for OrderMonoidHom
needs a proof of map_one
as well as map_mul
; a separate
constructor OrderMonoidHom.mk'
will construct ordered group homs (i.e. ordered monoid homs
between ordered groups) given only a proof that multiplication is preserved,
Implicit {}
brackets are often used instead of type class []
brackets. This is done when the
instances can be inferred because they are implicit arguments to the type OrderMonoidHom
. When
they can be inferred from the type it is faster to use this method than to use type class inference.
Removed typeclasses #
This file used to define typeclasses for order-preserving (additive) monoid homomorphisms:
OrderAddMonoidHomClass
, OrderMonoidHomClass
, and OrderMonoidWithZeroHomClass
.
In https://github.com/leanprover-community/mathlib4/pull/10544 we migrated from these typeclasses
to assumptions like [FunLike F M N] [MonoidHomClass F M N] [OrderHomClass F M N]
,
making some definitions and lemmas irrelevant.
Tags #
ordered monoid, ordered group, monoid with zero
α →+o β
is the type of monotone functions α → β
that preserve the OrderedAddCommMonoid
structure.
OrderAddMonoidHom
is also used for ordered group homomorphisms.
When possible, instead of parametrizing results over (f : α →+o β)
,
you should parametrize over
(F : Type*) [FunLike F M N] [MonoidHomClass F M N] [OrderHomClass F M N] (f : F)
.
- toFun : α → β
- map_add' (x y : α) : (↑self.toAddMonoidHom).toFun (x + y) = (↑self.toAddMonoidHom).toFun x + (↑self.toAddMonoidHom).toFun y
- monotone' : Monotone (↑self.toAddMonoidHom).toFun
An
OrderAddMonoidHom
is a monotone function.
Instances For
α ≃+o β
is the type of monotone isomorphisms α ≃ β
that preserve the OrderedAddCommMonoid
structure.
OrderAddMonoidIso
is also used for ordered group isomorphisms.
When possible, instead of parametrizing results over (f : α ≃+o β)
,
you should parametrize over
(F : Type*) [FunLike F M N] [AddEquivClass F M N] [OrderIsoClass F M N] (f : F)
.
- toFun : α → β
- invFun : β → α
- left_inv : Function.LeftInverse self.invFun self.toFun
- right_inv : Function.RightInverse self.invFun self.toFun
An
OrderAddMonoidIso
respects≤
.
Instances For
α →*o β
is the type of functions α → β
that preserve the OrderedCommMonoid
structure.
OrderMonoidHom
is also used for ordered group homomorphisms.
When possible, instead of parametrizing results over (f : α →*o β)
,
you should parametrize over
(F : Type*) [FunLike F M N] [MonoidHomClass F M N] [OrderHomClass F M N] (f : F)
.
- toFun : α → β
- map_mul' (x y : α) : (↑self.toMonoidHom).toFun (x * y) = (↑self.toMonoidHom).toFun x * (↑self.toMonoidHom).toFun y
- monotone' : Monotone (↑self.toMonoidHom).toFun
An
OrderMonoidHom
is a monotone function.
Instances For
Turn an element of a type F
satisfying OrderHomClass F α β
and MonoidHomClass F α β
into an actual OrderMonoidHom
. This is declared as the default coercion from F
to α →*o β
.
Equations
Instances For
Turn an element of a type F
satisfying OrderHomClass F α β
and AddMonoidHomClass F α β
into an actual OrderAddMonoidHom
.
This is declared as the default coercion from F
to α →+o β
.
Equations
Instances For
Any type satisfying OrderMonoidHomClass
can be cast into OrderMonoidHom
via
OrderMonoidHomClass.toOrderMonoidHom
.
Equations
Any type satisfying OrderAddMonoidHomClass
can be cast into OrderAddMonoidHom
via
OrderAddMonoidHomClass.toOrderAddMonoidHom
Equations
α ≃*o β
is the type of isomorphisms α ≃ β
that preserve the OrderedCommMonoid
structure.
OrderMonoidIso
is also used for ordered group isomorphisms.
When possible, instead of parametrizing results over (f : α ≃*o β)
,
you should parametrize over
(F : Type*) [FunLike F M N] [MulEquivClass F M N] [OrderIsoClass F M N] (f : F)
.
- toFun : α → β
- invFun : β → α
- left_inv : Function.LeftInverse self.invFun self.toFun
- right_inv : Function.RightInverse self.invFun self.toFun
An
OrderMonoidIso
respects≤
.
Instances For
Turn an element of a type F
satisfying OrderIsoClass F α β
and MulEquivClass F α β
into an actual OrderMonoidIso
. This is declared as the default coercion from F
to α ≃*o β
.
Equations
Instances For
Turn an element of a type F
satisfying OrderIsoClass F α β
and AddEquivClass F α β
into an actual OrderAddMonoidIso
.
This is declared as the default coercion from F
to α ≃+o β
.
Equations
Instances For
Any type satisfying OrderMonoidHomClass
can be cast into OrderMonoidHom
via
OrderMonoidHomClass.toOrderMonoidHom
.
Equations
Any type satisfying OrderAddMonoidHomClass
can be cast into OrderAddMonoidHom
via
OrderAddMonoidHomClass.toOrderAddMonoidHom
Equations
Any type satisfying OrderMonoidIsoClass
can be cast into OrderMonoidIso
via
OrderMonoidIsoClass.toOrderMonoidIso
.
Equations
Any type satisfying OrderAddMonoidIsoClass
can be cast into OrderAddMonoidIso
via
OrderAddMonoidIsoClass.toOrderAddMonoidIso
Equations
OrderMonoidWithZeroHom α β
is the type of functions α → β
that preserve
the MonoidWithZero
structure.
OrderMonoidWithZeroHom
is also used for group homomorphisms.
When possible, instead of parametrizing results over (f : α →+ β)
,
you should parameterize over
(F : Type*) [FunLike F M N] [MonoidWithZeroHomClass F M N] [OrderHomClass F M N] (f : F)
.
- toFun : α → β
- map_mul' (x y : α) : (↑self.toMonoidWithZeroHom).toFun (x * y) = (↑self.toMonoidWithZeroHom).toFun x * (↑self.toMonoidWithZeroHom).toFun y
- monotone' : Monotone (↑self.toMonoidWithZeroHom).toFun
An
OrderMonoidWithZeroHom
is a monotone function.
Instances For
Turn an element of a type F
satisfying OrderHomClass F α β
and MonoidWithZeroHomClass F α β
into an actual OrderMonoidWithZeroHom
.
This is declared as the default coercion from F
to α →+*₀o β
.
Equations
Instances For
Equations
See also NonnegHomClass.apply_nonneg
.
Equations
Equations
Reinterpret an ordered monoid homomorphism as an order homomorphism.
Equations
Instances For
Reinterpret an ordered additive monoid homomorphism as an order homomorphism.
Equations
Instances For
Copy of an OrderMonoidHom
with a new toFun
equal to the old one. Useful to fix
definitional equalities.
Equations
Instances For
Copy of an OrderAddMonoidHom
with a new toFun
equal to the old one. Useful to fix
definitional equalities.
Equations
Instances For
The identity map as an ordered monoid homomorphism.
Equations
Instances For
The identity map as an ordered additive monoid homomorphism.
Equations
Instances For
Equations
Equations
Composition of OrderMonoidHom
s as an OrderMonoidHom
.
Equations
Instances For
Composition of OrderAddMonoidHom
s as an OrderAddMonoidHom
Equations
Instances For
1
is the homomorphism sending all elements to 1
.
Equations
0
is the homomorphism sending all elements to 0
.
Equations
For two ordered monoid morphisms f
and g
, their product is the ordered monoid morphism
sending a
to f a * g a
.
Equations
For two ordered additive monoid morphisms f
and g
, their product is the ordered
additive monoid morphism sending a
to f a + g a
.
Equations
Makes an ordered group homomorphism from a proof that the map preserves multiplication.
Equations
Instances For
Makes an ordered additive group homomorphism from a proof that the map preserves addition.
Equations
Instances For
Makes an ordered group isomorphism from a proof that the map preserves multiplication.
Equations
Instances For
Makes an ordered additive group isomorphism from a proof that the map preserves addition.
Equations
Instances For
Equations
Reinterpret an ordered monoid with zero homomorphism as an order monoid homomorphism.
Equations
Instances For
Copy of an OrderMonoidWithZeroHom
with a new toFun
equal to the old one. Useful to fix
definitional equalities.
Equations
Instances For
The identity map as an ordered monoid with zero homomorphism.
Equations
Instances For
Equations
Composition of OrderMonoidWithZeroHom
s as an OrderMonoidWithZeroHom
.
Equations
Instances For
For two ordered monoid morphisms f
and g
, their product is the ordered monoid morphism
sending a
to f a * g a
.