doc-next-gen

Mathlib.Algebra.Order.Interval.Set.Instances

Module docstring

{"# Algebraic instances for unit intervals

For suitably structured underlying type α, we exhibit the structure of the unit intervals (Set.Icc, Set.Ioc, Set.Ioc, and Set.Ioo) from 0 to 1. Note: Instances for the interval Ici 0 are dealt with in Algebra/Order/Nonneg.lean.

Main definitions

The strongest typeclass provided on each interval is: * Set.Icc.cancelCommMonoidWithZero * Set.Ico.commSemigroup * Set.Ioc.commMonoid * Set.Ioo.commSemigroup

TODO

  • algebraic instances for intervals -1 to 1
  • algebraic instances for Ici 1
  • algebraic instances for (Ioo (-1) 1)ᶜ
  • provide distribNeg instances where applicable
  • prove versions of mul_le_{left,right} for other intervals
  • prove versions of the lemmas in Topology/UnitInterval with generalized to some arbitrary ordered semiring ","### Instances for ↥(Set.Icc 0 1) ","### Instances for ↥(Set.Ico 0 1) ","### Instances for ↥(Set.Ioc 0 1) ","### Instances for ↥(Set.Ioo 0 1) "}
Set.Icc.zero instance
: Zero (Icc (0 : R) 1)
Full source
instance zero : Zero (Icc (0 : R) 1) where zero := ⟨0, left_mem_Icc.2 zero_le_one⟩
The Zero Element in the Unit Interval
Informal description
The closed interval $[0, 1]$ in an ordered semiring $R$ has a canonical zero element, which is the element $0 \in R$ restricted to the interval.
Set.Icc.one instance
: One (Icc (0 : R) 1)
Full source
instance one : One (Icc (0 : R) 1) where one := ⟨1, right_mem_Icc.2 zero_le_one⟩
The One Element in the Unit Interval
Informal description
The closed interval $[0, 1]$ in an ordered semiring $R$ has a canonical one element, which is the element $1 \in R$ restricted to the interval.
Set.Icc.coe_zero theorem
: ↑(0 : Icc (0 : R) 1) = (0 : R)
Full source
@[simp, norm_cast]
theorem coe_zero : ↑(0 : Icc (0 : R) 1) = (0 : R) :=
  rfl
Embedding of Zero in Unit Interval Equals Zero in Semiring
Informal description
The canonical embedding of the zero element in the closed unit interval $[0,1]$ of an ordered semiring $R$ is equal to the zero element of $R$, i.e., $\uparrow(0 : [0,1]) = (0 : R)$.
Set.Icc.coe_one theorem
: ↑(1 : Icc (0 : R) 1) = (1 : R)
Full source
@[simp, norm_cast]
theorem coe_one : ↑(1 : Icc (0 : R) 1) = (1 : R) :=
  rfl
Embedding of One in Unit Interval Equals One in Semiring
Informal description
The canonical embedding of the element $1$ in the closed unit interval $[0, 1]$ of an ordered semiring $R$ is equal to the element $1$ in $R$.
Set.Icc.mk_zero theorem
(h : (0 : R) ∈ Icc (0 : R) 1) : (⟨0, h⟩ : Icc (0 : R) 1) = 0
Full source
@[simp]
theorem mk_zero (h : (0 : R) ∈ Icc (0 : R) 1) : (⟨0, h⟩ : Icc (0 : R) 1) = 0 :=
  rfl
Zero Element Construction in Unit Interval
Informal description
For any ordered semiring $R$, if $0 \in [0,1]$, then the element $\langle 0, h \rangle$ in the closed interval $[0,1]$ is equal to the zero element of the interval.
Set.Icc.mk_one theorem
(h : (1 : R) ∈ Icc (0 : R) 1) : (⟨1, h⟩ : Icc (0 : R) 1) = 1
Full source
@[simp]
theorem mk_one (h : (1 : R) ∈ Icc (0 : R) 1) : (⟨1, h⟩ : Icc (0 : R) 1) = 1 :=
  rfl
Canonical One Element in Unit Interval
Informal description
For any ordered semiring $R$, if $1$ is an element of the closed interval $[0, 1]$, then the element $\langle 1, h \rangle$ in the subtype $[0, 1]$ is equal to the canonical one element of $[0, 1]$.
Set.Icc.coe_eq_zero theorem
{x : Icc (0 : R) 1} : (x : R) = 0 ↔ x = 0
Full source
@[simp, norm_cast]
theorem coe_eq_zero {x : Icc (0 : R) 1} : (x : R) = 0 ↔ x = 0 := by
  symm
  exact Subtype.ext_iff
Characterization of Zero in the Unit Interval: $x = 0 \leftrightarrow x = 0$ in $[0,1]$
Informal description
For any element $x$ in the closed unit interval $[0, 1]$ of an ordered semiring $R$, the underlying value of $x$ in $R$ is equal to $0$ if and only if $x$ is the zero element of the interval.
Set.Icc.coe_ne_zero theorem
{x : Icc (0 : R) 1} : (x : R) ≠ 0 ↔ x ≠ 0
Full source
theorem coe_ne_zero {x : Icc (0 : R) 1} : (x : R) ≠ 0(x : R) ≠ 0 ↔ x ≠ 0 :=
  not_iff_not.mpr coe_eq_zero
Nonzero Characterization in Unit Interval: $(x : R) \neq 0 \leftrightarrow x \neq 0$ for $x \in [0,1]$
Informal description
For any element $x$ in the closed unit interval $[0, 1]$ of an ordered semiring $R$, the underlying value of $x$ in $R$ is not equal to $0$ if and only if $x$ is not the zero element of the interval.
Set.Icc.coe_eq_one theorem
{x : Icc (0 : R) 1} : (x : R) = 1 ↔ x = 1
Full source
@[simp, norm_cast]
theorem coe_eq_one {x : Icc (0 : R) 1} : (x : R) = 1 ↔ x = 1 := by
  symm
  exact Subtype.ext_iff
Characterization of One in Unit Interval: $(x : R) = 1 \leftrightarrow x = 1$ for $x \in [0,1]$
Informal description
For any element $x$ in the closed interval $[0,1]$ of an ordered semiring $R$, the underlying value of $x$ in $R$ equals $1$ if and only if $x$ is equal to the canonical one element of the interval.
Set.Icc.coe_ne_one theorem
{x : Icc (0 : R) 1} : (x : R) ≠ 1 ↔ x ≠ 1
Full source
theorem coe_ne_one {x : Icc (0 : R) 1} : (x : R) ≠ 1(x : R) ≠ 1 ↔ x ≠ 1 :=
  not_iff_not.mpr coe_eq_one
Characterization of Non-One Elements in Unit Interval: $(x : R) \neq 1 \leftrightarrow x \neq 1$ for $x \in [0,1]$
Informal description
For any element $x$ in the closed interval $[0,1]$ of an ordered semiring $R$, the underlying value of $x$ in $R$ is not equal to $1$ if and only if $x$ is not equal to the canonical one element of the interval.
Set.Icc.coe_nonneg theorem
(x : Icc (0 : R) 1) : 0 ≤ (x : R)
Full source
theorem coe_nonneg (x : Icc (0 : R) 1) : 0 ≤ (x : R) :=
  x.2.1
Nonnegativity of Elements in Unit Interval $[0,1]$
Informal description
For any element $x$ in the closed interval $[0,1]$ of a partially ordered type $R$, the underlying value of $x$ (when viewed as an element of $R$) is nonnegative, i.e., $0 \leq x$.
Set.Icc.coe_le_one theorem
(x : Icc (0 : R) 1) : (x : R) ≤ 1
Full source
theorem coe_le_one (x : Icc (0 : R) 1) : (x : R) ≤ 1 :=
  x.2.2
Upper Bound for Elements in Unit Interval $[0, 1]$
Informal description
For any element $x$ in the closed interval $[0, 1]$ of a type $R$ with a partial order, the underlying value of $x$ (when viewed as an element of $R$) is less than or equal to $1$, i.e., $x \leq 1$.
Set.Icc.nonneg theorem
{t : Icc (0 : R) 1} : 0 ≤ t
Full source
/-- like `coe_nonneg`, but with the inequality in `Icc (0:R) 1`. -/
theorem nonneg {t : Icc (0 : R) 1} : 0 ≤ t :=
  t.2.1
Nonnegativity of Elements in the Unit Interval $[0,1]$
Informal description
For any element $t$ in the closed interval $[0, 1]$ of an ordered semiring $R$, we have $0 \leq t$.
Set.Icc.le_one theorem
{t : Icc (0 : R) 1} : t ≤ 1
Full source
/-- like `coe_le_one`, but with the inequality in `Icc (0:R) 1`. -/
theorem le_one {t : Icc (0 : R) 1} : t ≤ 1 :=
  t.2.2
Upper bound property of the unit interval $[0, 1]$
Informal description
For any element $t$ in the closed interval $[0, 1]$ of an ordered semiring $R$, we have $t \leq 1$.
Set.Icc.mul instance
: Mul (Icc (0 : R) 1)
Full source
instance mul : Mul (Icc (0 : R) 1) where
  mul p q := ⟨p * q, ⟨mul_nonneg p.2.1 q.2.1, mul_le_one₀ p.2.2 q.2.1 q.2.2⟩⟩
Multiplication Operation on the Unit Interval $[0, 1]$
Informal description
For any ordered semiring $R$, the closed interval $[0, 1]$ in $R$ is equipped with a multiplication operation, where for any $x, y \in [0, 1]$, the product $x \cdot y$ is defined as the multiplication of $x$ and $y$ in $R$.
Set.Icc.pow instance
: Pow (Icc (0 : R) 1) ℕ
Full source
instance pow : Pow (Icc (0 : R) 1)  where
  pow p n := ⟨p.1 ^ n, ⟨pow_nonneg p.2.1 n, pow_le_one₀ p.2.1 p.2.2⟩⟩
Natural Power Operation on the Unit Interval $[0, 1]$
Informal description
For any ordered semiring $R$, the closed interval $[0, 1]$ in $R$ is equipped with a natural power operation, where for any $x \in [0, 1]$ and natural number $n$, the power $x^n$ is defined as the $n$-fold multiplication of $x$ in $R$.
Set.Icc.coe_mul theorem
(x y : Icc (0 : R) 1) : ↑(x * y) = (x * y : R)
Full source
@[simp, norm_cast]
theorem coe_mul (x y : Icc (0 : R) 1) : ↑(x * y) = (x * y : R) :=
  rfl
Embedding Preserves Multiplication in Unit Interval $[0, 1]$
Informal description
For any elements $x, y$ in the closed interval $[0, 1]$ of an ordered semiring $R$, the canonical embedding of their product in $R$ equals the product of their embeddings, i.e., $(x \cdot y) = (x : R) \cdot (y : R)$.
Set.Icc.coe_pow theorem
(x : Icc (0 : R) 1) (n : ℕ) : ↑(x ^ n) = ((x : R) ^ n)
Full source
@[simp, norm_cast]
theorem coe_pow (x : Icc (0 : R) 1) (n : ) : ↑(x ^ n) = ((x : R) ^ n) :=
  rfl
Power Operation Commutes with Inclusion on Unit Interval
Informal description
For any element $x$ in the closed interval $[0, 1]$ of an ordered semiring $R$ and any natural number $n$, the canonical inclusion map $\uparrow$ from $[0, 1]$ to $R$ satisfies $\uparrow(x^n) = (\uparrow x)^n$.
Set.Icc.mul_le_left theorem
{x y : Icc (0 : R) 1} : x * y ≤ x
Full source
theorem mul_le_left {x y : Icc (0 : R) 1} : x * y ≤ x :=
  (mul_le_mul_of_nonneg_left y.2.2 x.2.1).trans_eq (mul_one _)
Left Multiplication Inequality in Unit Interval: $x \cdot y \leq x$ for $x, y \in [0,1]$
Informal description
For any elements $x, y$ in the closed unit interval $[0, 1]$ of an ordered semiring $R$, the product $x \cdot y$ is less than or equal to $x$.
Set.Icc.mul_le_right theorem
{x y : Icc (0 : R) 1} : x * y ≤ y
Full source
theorem mul_le_right {x y : Icc (0 : R) 1} : x * y ≤ y :=
  (mul_le_mul_of_nonneg_right x.2.2 y.2.1).trans_eq (one_mul _)
Right Multiplication Inequality in Unit Interval: $x \cdot y \leq y$ for $x, y \in [0,1]$
Informal description
For any elements $x, y$ in the closed interval $[0, 1]$ of an ordered semiring $R$, the product $x \cdot y$ is less than or equal to $y$.
Set.Icc.monoidWithZero instance
: MonoidWithZero (Icc (0 : R) 1)
Full source
instance monoidWithZero : MonoidWithZero (Icc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.monoidWithZero _ coe_zero coe_one coe_mul coe_pow
Monoid with Zero Structure on the Unit Interval $[0, 1]$
Informal description
For any ordered semiring $R$, the closed unit interval $[0, 1]$ in $R$ forms a monoid with zero. This means it has an associative multiplication operation with an identity element $1$ and a zero element $0$, where $0$ acts as an absorbing element (i.e., $0 \cdot x = x \cdot 0 = 0$ for all $x \in [0, 1]$).
Set.Icc.commMonoidWithZero instance
{R : Type*} [CommSemiring R] [PartialOrder R] [IsOrderedRing R] : CommMonoidWithZero (Icc (0 : R) 1)
Full source
instance commMonoidWithZero {R : Type*} [CommSemiring R] [PartialOrder R] [IsOrderedRing R] :
    CommMonoidWithZero (Icc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.commMonoidWithZero _ coe_zero coe_one coe_mul coe_pow
Commutative Monoid with Zero Structure on the Unit Interval $[0, 1]$
Informal description
For any commutative semiring $R$ with a partial order and the structure of an ordered ring, the closed unit interval $[0, 1]$ in $R$ forms a commutative monoid with zero. This means it has an associative and commutative multiplication operation with an identity element $1$ and a zero element $0$, where $0$ acts as an absorbing element (i.e., $0 \cdot x = x \cdot 0 = 0$ for all $x \in [0, 1]$).
Set.Icc.cancelMonoidWithZero instance
{R : Type*} [Ring R] [PartialOrder R] [IsOrderedRing R] [NoZeroDivisors R] : CancelMonoidWithZero (Icc (0 : R) 1)
Full source
instance cancelMonoidWithZero {R : Type*} [Ring R] [PartialOrder R] [IsOrderedRing R]
    [NoZeroDivisors R] :
    CancelMonoidWithZero (Icc (0 : R) 1) := fast_instance%
  @Function.Injective.cancelMonoidWithZero R _ NoZeroDivisors.toCancelMonoidWithZero _ _ _ _
    (fun v => v.val) Subtype.coe_injective coe_zero coe_one coe_mul coe_pow
Cancelative Monoid with Zero Structure on the Unit Interval $[0, 1]$
Informal description
For any ordered ring $R$ with no zero divisors, the closed unit interval $[0, 1]$ forms a cancelative monoid with zero. This means it has an associative and commutative multiplication operation with an identity element $1$ and a zero element $0$, where $0$ acts as an absorbing element, and the cancellation property holds: if $x \cdot y = x \cdot z$ and $x \neq 0$, then $y = z$ for all $x, y, z \in [0, 1]$.
Set.Icc.cancelCommMonoidWithZero instance
{R : Type*} [CommRing R] [PartialOrder R] [IsOrderedRing R] [NoZeroDivisors R] : CancelCommMonoidWithZero (Icc (0 : R) 1)
Full source
instance cancelCommMonoidWithZero {R : Type*} [CommRing R] [PartialOrder R] [IsOrderedRing R]
    [NoZeroDivisors R] :
    CancelCommMonoidWithZero (Icc (0 : R) 1) := fast_instance%
  @Function.Injective.cancelCommMonoidWithZero R _ NoZeroDivisors.toCancelCommMonoidWithZero _ _ _ _
    (fun v => v.val) Subtype.coe_injective coe_zero coe_one coe_mul coe_pow
Cancelative Commutative Monoid with Zero Structure on $[0,1]$
Informal description
For any commutative ordered ring $R$ with no zero divisors, the closed unit interval $[0, 1]$ forms a cancelative commutative monoid with zero. This means it has an associative and commutative multiplication operation with an identity element $1$ and a zero element $0$, where $0$ acts as an absorbing element, and the cancellation property holds: if $x \cdot y = x \cdot z$ and $x \neq 0$, then $y = z$ for all $x, y, z \in [0, 1]$.
Set.Icc.mem_iff_one_sub_mem theorem
{t : β} : t ∈ Icc (0 : β) 1 ↔ 1 - t ∈ Icc (0 : β) 1
Full source
theorem mem_iff_one_sub_mem {t : β} : t ∈ Icc (0 : β) 1t ∈ Icc (0 : β) 1 ↔ 1 - t ∈ Icc (0 : β) 1 :=
  ⟨one_sub_mem, fun h => sub_sub_cancel 1 t ▸ one_sub_mem h⟩
Characterization of Unit Interval Membership via $1 - t$
Informal description
For any element $t$ in an ordered semiring $\beta$, $t$ belongs to the closed interval $[0,1]$ if and only if $1 - t$ belongs to $[0,1]$. In other words, $t \in [0,1] \leftrightarrow 1 - t \in [0,1]$.
Set.Icc.one_sub_nonneg theorem
(x : Icc (0 : β) 1) : 0 ≤ 1 - (x : β)
Full source
theorem one_sub_nonneg (x : Icc (0 : β) 1) : 0 ≤ 1 - (x : β) := by simpa using x.2.2
Nonnegativity of $1 - x$ in the unit interval
Informal description
For any element $x$ in the closed interval $[0, 1]$ of an ordered semiring $\beta$, the difference $1 - x$ is nonnegative, i.e., $0 \leq 1 - x$.
Set.Icc.one_sub_le_one theorem
(x : Icc (0 : β) 1) : 1 - (x : β) ≤ 1
Full source
theorem one_sub_le_one (x : Icc (0 : β) 1) : 1 - (x : β) ≤ 1 := by simpa using x.2.1
Upper bound for $1 - x$ in the unit interval
Informal description
For any element $x$ in the closed interval $[0, 1]$ of an ordered semiring $\beta$, the difference $1 - x$ is less than or equal to $1$.
Set.Ico.zero instance
[Nontrivial R] : Zero (Ico (0 : R) 1)
Full source
instance zero [Nontrivial R] : Zero (Ico (0 : R) 1) where zero := ⟨0, left_mem_Ico.2 zero_lt_one⟩
Zero Element in the Interval [0,1)
Informal description
For any nontrivial ordered semiring $R$, the left-closed right-open interval $[0, 1)$ has a zero element.
Set.Ico.coe_zero theorem
[Nontrivial R] : ↑(0 : Ico (0 : R) 1) = (0 : R)
Full source
@[simp, norm_cast]
theorem coe_zero [Nontrivial R] : ↑(0 : Ico (0 : R) 1) = (0 : R) :=
  rfl
Embedding of Zero in $[0,1)$ Matches Zero in $R$
Informal description
For any nontrivial ordered semiring $R$, the canonical embedding of the zero element in the interval $[0, 1)$ into $R$ is equal to the zero element of $R$. That is, if $0_{[0,1)}$ denotes the zero element of $[0, 1)$, then $0_{[0,1)} = 0_R$ under the embedding.
Set.Ico.mk_zero theorem
[Nontrivial R] (h : (0 : R) ∈ Ico (0 : R) 1) : (⟨0, h⟩ : Ico (0 : R) 1) = 0
Full source
@[simp]
theorem mk_zero [Nontrivial R] (h : (0 : R) ∈ Ico (0 : R) 1) : (⟨0, h⟩ : Ico (0 : R) 1) = 0 :=
  rfl
Zero Construction in Interval $[0,1)$
Informal description
For any nontrivial ordered semiring $R$, if $0$ is an element of the interval $[0,1)$, then the element $\langle 0, h \rangle$ in the interval $[0,1)$ is equal to the zero element of the interval.
Set.Ico.coe_eq_zero theorem
[Nontrivial R] {x : Ico (0 : R) 1} : (x : R) = 0 ↔ x = 0
Full source
@[simp, norm_cast]
theorem coe_eq_zero [Nontrivial R] {x : Ico (0 : R) 1} : (x : R) = 0 ↔ x = 0 := by
  symm
  exact Subtype.ext_iff
Characterization of Zero in the Interval [0,1)
Informal description
Let $R$ be a nontrivial ordered semiring. For any element $x$ in the interval $[0, 1) \subseteq R$, the equality $x = 0$ holds in $R$ if and only if $x$ is equal to the zero element of the interval $[0, 1)$.
Set.Ico.coe_ne_zero theorem
[Nontrivial R] {x : Ico (0 : R) 1} : (x : R) ≠ 0 ↔ x ≠ 0
Full source
theorem coe_ne_zero [Nontrivial R] {x : Ico (0 : R) 1} : (x : R) ≠ 0(x : R) ≠ 0 ↔ x ≠ 0 :=
  not_iff_not.mpr coe_eq_zero
Nonzero Characterization in $[0,1)$: $x \neq 0 \leftrightarrow x \neq 0$
Informal description
Let $R$ be a nontrivial ordered semiring. For any element $x$ in the interval $[0, 1) \subseteq R$, the inequality $x \neq 0$ holds in $R$ if and only if $x$ is not equal to the zero element of the interval $[0, 1)$.
Set.Ico.coe_nonneg theorem
(x : Ico (0 : R) 1) : 0 ≤ (x : R)
Full source
theorem coe_nonneg (x : Ico (0 : R) 1) : 0 ≤ (x : R) :=
  x.2.1
Nonnegativity of Elements in $[0, 1)$ Interval
Informal description
For any element $x$ in the left-closed right-open interval $[0, 1)$ of a type $R$ with a partial order, the value of $x$ (when viewed as an element of $R$) is nonnegative, i.e., $0 \leq x$.
Set.Ico.coe_lt_one theorem
(x : Ico (0 : R) 1) : (x : R) < 1
Full source
theorem coe_lt_one (x : Ico (0 : R) 1) : (x : R) < 1 :=
  x.2.2
Elements of $[0,1)$ are strictly less than 1
Informal description
For any element $x$ in the left-closed right-open interval $[0,1)$ of a type $R$ with a partial order, the value of $x$ (when viewed as an element of $R$) is strictly less than 1, i.e., $x < 1$.
Set.Ico.nonneg theorem
[Nontrivial R] {t : Ico (0 : R) 1} : 0 ≤ t
Full source
/-- like `coe_nonneg`, but with the inequality in `Ico (0:R) 1`. -/
theorem nonneg [Nontrivial R] {t : Ico (0 : R) 1} : 0 ≤ t :=
  t.2.1
Nonnegativity of Elements in $[0,1)$ Interval
Informal description
For any nontrivial ordered semiring $R$ and any element $t$ in the left-closed right-open interval $[0,1)$, the element $t$ is nonnegative, i.e., $0 \leq t$.
Set.Ico.coe_mul theorem
(x y : Ico (0 : R) 1) : ↑(x * y) = (x * y : R)
Full source
@[simp, norm_cast]
theorem coe_mul (x y : Ico (0 : R) 1) : ↑(x * y) = (x * y : R) :=
  rfl
Embedding of Multiplication in $[0,1)$ Interval
Informal description
For any elements $x$ and $y$ in the left-closed right-open interval $[0,1)$ of an ordered semiring $R$, the canonical embedding of their product in $R$ equals the product of their embeddings, i.e., $\uparrow(x \cdot y) = (x \cdot y : R)$.
Set.Ico.semigroup instance
: Semigroup (Ico (0 : R) 1)
Full source
instance semigroup : Semigroup (Ico (0 : R) 1) := fast_instance%
  Subtype.coe_injective.semigroup _ coe_mul
Semigroup Structure on the Interval $[0,1)$
Informal description
For any ordered semiring $R$, the left-closed right-open interval $[0,1)$ forms a semigroup under the multiplication operation inherited from $R$.
Set.Ico.commSemigroup instance
{R : Type*} [CommSemiring R] [PartialOrder R] [IsOrderedRing R] : CommSemigroup (Ico (0 : R) 1)
Full source
instance commSemigroup {R : Type*} [CommSemiring R] [PartialOrder R] [IsOrderedRing R] :
    CommSemigroup (Ico (0 : R) 1) := fast_instance%
  Subtype.coe_injective.commSemigroup _ coe_mul
Commutative Semigroup Structure on $[0,1)$ in Ordered Commutative Semirings
Informal description
For any commutative semiring $R$ with a partial order and the structure of an ordered ring, the left-closed right-open interval $[0,1)$ forms a commutative semigroup under the multiplication operation inherited from $R$.
Set.Ioc.one instance
: One (Ioc (0 : R) 1)
Full source
instance one : One (Ioc (0 : R) 1) where one := ⟨1, ⟨zero_lt_one, le_refl 1⟩⟩
Multiplicative Identity in the Interval (0, 1]
Informal description
For any strictly ordered semiring $R$, the left-open right-closed interval $(0, 1]$ in $R$ has a canonical multiplicative identity element.
Set.Ioc.coe_one theorem
: ↑(1 : Ioc (0 : R) 1) = (1 : R)
Full source
@[simp, norm_cast]
theorem coe_one : ↑(1 : Ioc (0 : R) 1) = (1 : R) :=
  rfl
Inclusion of the Identity in $(0, 1]$ Maps to $1$ in $R$
Informal description
The canonical inclusion map from the multiplicative identity element in the interval $(0, 1]$ of a strictly ordered semiring $R$ to $R$ itself maps the identity element to the multiplicative identity $1$ in $R$. In other words, if $1$ is considered as an element of $(0, 1]$, then its image under the inclusion map is $1 \in R$.
Set.Ioc.mk_one theorem
(h : (1 : R) ∈ Ioc (0 : R) 1) : (⟨1, h⟩ : Ioc (0 : R) 1) = 1
Full source
@[simp]
theorem mk_one (h : (1 : R) ∈ Ioc (0 : R) 1) : (⟨1, h⟩ : Ioc (0 : R) 1) = 1 :=
  rfl
Construction of Multiplicative Identity in Interval (0, 1]
Informal description
For any strictly ordered semiring $R$, if $1$ is an element of the interval $(0, 1]$, then the element $\langle 1, h \rangle$ of the interval $(0, 1]$ is equal to the multiplicative identity $1$ in $(0, 1]$.
Set.Ioc.coe_eq_one theorem
{x : Ioc (0 : R) 1} : (x : R) = 1 ↔ x = 1
Full source
@[simp, norm_cast]
theorem coe_eq_one {x : Ioc (0 : R) 1} : (x : R) = 1 ↔ x = 1 := by
  symm
  exact Subtype.ext_iff
Characterization of the Multiplicative Identity in $(0,1]$ Interval
Informal description
For any element $x$ in the left-open right-closed interval $(0, 1]$ of a strictly ordered semiring $R$, the underlying value of $x$ in $R$ equals $1$ if and only if $x$ is the multiplicative identity element of the interval.
Set.Ioc.coe_ne_one theorem
{x : Ioc (0 : R) 1} : (x : R) ≠ 1 ↔ x ≠ 1
Full source
theorem coe_ne_one {x : Ioc (0 : R) 1} : (x : R) ≠ 1(x : R) ≠ 1 ↔ x ≠ 1 :=
  not_iff_not.mpr coe_eq_one
Negation of Multiplicative Identity in $(0,1]$ Interval: $(x : R) \neq 1 \leftrightarrow x \neq 1$
Informal description
For any element $x$ in the left-open right-closed interval $(0, 1]$ of a strictly ordered semiring $R$, the underlying value of $x$ in $R$ is not equal to $1$ if and only if $x$ is not the multiplicative identity element of the interval.
Set.Ioc.coe_pos theorem
(x : Ioc (0 : R) 1) : 0 < (x : R)
Full source
theorem coe_pos (x : Ioc (0 : R) 1) : 0 < (x : R) :=
  x.2.1
Positivity of Elements in $(0,1]$ Interval
Informal description
For any element $x$ in the left-open right-closed interval $(0, 1]$ of a partially ordered type $R$, the underlying value of $x$ in $R$ satisfies $0 < (x : R)$.
Set.Ioc.coe_le_one theorem
(x : Ioc (0 : R) 1) : (x : R) ≤ 1
Full source
theorem coe_le_one (x : Ioc (0 : R) 1) : (x : R) ≤ 1 :=
  x.2.2
Elements of $(0,1]$ are bounded above by 1
Informal description
For any element $x$ in the left-open right-closed interval $(0, 1]$ of a type $R$ with a partial order, the underlying value of $x$ in $R$ satisfies $(x : R) \leq 1$.
Set.Ioc.le_one theorem
{t : Ioc (0 : R) 1} : t ≤ 1
Full source
/-- like `coe_le_one`, but with the inequality in `Ioc (0:R) 1`. -/
theorem le_one {t : Ioc (0 : R) 1} : t ≤ 1 :=
  t.2.2
Upper Bound of Elements in $(0,1]$ Interval
Informal description
For any element $t$ in the left-open right-closed interval $(0, 1]$ of a strictly ordered semiring $R$, we have $t \leq 1$.
Set.Ioc.pow instance
: Pow (Ioc (0 : R) 1) ℕ
Full source
instance pow : Pow (Ioc (0 : R) 1)  where
  pow p n := ⟨p.1 ^ n, ⟨pow_pos p.2.1 n, pow_le_one₀ (le_of_lt p.2.1) p.2.2⟩⟩
Natural Power Operation on the Interval (0, 1] in Ordered Semirings
Informal description
For any strict ordered semiring $R$, the left-open right-closed interval $(0, 1]$ is equipped with a natural power operation, where for any $x \in (0, 1]$ and natural number $n$, the power $x^n$ is defined as the $n$-fold multiplication of $x$ in $R$.
Set.Ioc.coe_mul theorem
(x y : Ioc (0 : R) 1) : ↑(x * y) = (x * y : R)
Full source
@[simp, norm_cast]
theorem coe_mul (x y : Ioc (0 : R) 1) : ↑(x * y) = (x * y : R) :=
  rfl
Embedding Preserves Multiplication in $(0, 1]$ Interval
Informal description
For any elements $x$ and $y$ in the left-open right-closed interval $(0, 1]$ of a strict ordered semiring $R$, the canonical embedding of their product in $R$ equals the product of their embeddings, i.e., $\uparrow(x * y) = (\uparrow x) * (\uparrow y)$ in $R$.
Set.Ioc.coe_pow theorem
(x : Ioc (0 : R) 1) (n : ℕ) : ↑(x ^ n) = ((x : R) ^ n)
Full source
@[simp, norm_cast]
theorem coe_pow (x : Ioc (0 : R) 1) (n : ) : ↑(x ^ n) = ((x : R) ^ n) :=
  rfl
Power Operation Commutes with Embedding in $(0, 1]$ Interval
Informal description
For any element $x$ in the left-open right-closed interval $(0, 1]$ of a strict ordered semiring $R$ and any natural number $n$, the canonical embedding of $x^n$ into $R$ equals the $n$-th power of $x$ in $R$, i.e., $\overline{x^n} = x^n$.
Set.Ioc.semigroup instance
: Semigroup (Ioc (0 : R) 1)
Full source
instance semigroup : Semigroup (Ioc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.semigroup _ coe_mul
Semigroup Structure on the Interval (0, 1] in Ordered Semirings
Informal description
For any strict ordered semiring $R$, the left-open right-closed interval $(0, 1]$ forms a semigroup under the multiplication operation inherited from $R$.
Set.Ioc.monoid instance
: Monoid (Ioc (0 : R) 1)
Full source
instance monoid : Monoid (Ioc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.monoid _ coe_one coe_mul coe_pow
Monoid Structure on the Interval (0,1] in Ordered Semirings
Informal description
For any strict ordered semiring $R$, the left-open right-closed interval $(0,1]$ forms a monoid under the multiplication operation inherited from $R$, with $1$ as the multiplicative identity.
Set.Ioc.commSemigroup instance
{R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] : CommSemigroup (Ioc (0 : R) 1)
Full source
instance commSemigroup {R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] :
    CommSemigroup (Ioc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.commSemigroup _ coe_mul
Commutative Semigroup Structure on (0, 1] in Strict Ordered Commutative Semirings
Informal description
For any commutative semiring $R$ with a partial order and the structure of a strict ordered ring, the left-open right-closed interval $(0, 1]$ forms a commutative semigroup under multiplication.
Set.Ioc.commMonoid instance
{R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] : CommMonoid (Ioc (0 : R) 1)
Full source
instance commMonoid {R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] :
    CommMonoid (Ioc (0 : R) 1) := fast_instance%
  Subtype.coe_injective.commMonoid _ coe_one coe_mul coe_pow
Commutative Monoid Structure on the Interval (0,1] in Strict Ordered Commutative Semirings
Informal description
For any commutative semiring $R$ with a partial order and the structure of a strict ordered ring, the left-open right-closed interval $(0, 1]$ forms a commutative monoid under multiplication.
Set.Ioc.cancelMonoid instance
{R : Type*} [Ring R] [PartialOrder R] [IsStrictOrderedRing R] [IsDomain R] : CancelMonoid (Ioc (0 : R) 1)
Full source
instance cancelMonoid {R : Type*} [Ring R] [PartialOrder R] [IsStrictOrderedRing R] [IsDomain R] :
    CancelMonoid (Ioc (0 : R) 1) :=
  { Set.Ioc.monoid with
    mul_left_cancel := fun a _ _ h =>
      Subtype.ext <| mul_left_cancel₀ a.prop.1.ne' <| (congr_arg Subtype.val h :)
    mul_right_cancel := fun _ b _ h =>
      Subtype.ext <| mul_right_cancel₀ b.prop.1.ne' <| (congr_arg Subtype.val h :) }
Cancellative Monoid Structure on (0,1] in Strict Ordered Domains
Informal description
For any ring $R$ with a partial order that forms a strict ordered ring and is a domain, the left-open right-closed interval $(0,1]$ forms a cancellative monoid under multiplication.
Set.Ioc.cancelCommMonoid instance
{R : Type*} [CommRing R] [PartialOrder R] [IsStrictOrderedRing R] [IsDomain R] : CancelCommMonoid (Ioc (0 : R) 1)
Full source
instance cancelCommMonoid {R : Type*} [CommRing R] [PartialOrder R] [IsStrictOrderedRing R]
    [IsDomain R] :
    CancelCommMonoid (Ioc (0 : R) 1) :=
  { Set.Ioc.cancelMonoid, Set.Ioc.commMonoid with }
Cancellative Commutative Monoid Structure on (0,1] in Strict Ordered Domains
Informal description
For any commutative ring $R$ with a partial order that forms a strict ordered ring and is a domain, the left-open right-closed interval $(0,1]$ forms a cancellative commutative monoid under multiplication.
Set.Ioo.pos theorem
(x : Ioo (0 : R) 1) : 0 < (x : R)
Full source
theorem pos (x : Ioo (0 : R) 1) : 0 < (x : R) :=
  x.2.1
Positivity in Open Unit Interval: $0 < x$ for $x \in (0,1)$
Informal description
For any element $x$ in the open interval $(0, 1)$ of a partially ordered ring $R$, the value of $x$ is strictly greater than $0$.
Set.Ioo.lt_one theorem
(x : Ioo (0 : R) 1) : (x : R) < 1
Full source
theorem lt_one (x : Ioo (0 : R) 1) : (x : R) < 1 :=
  x.2.2
Upper Bound of Open Unit Interval: $x < 1$ for $x \in (0,1)$
Informal description
For any element $x$ in the open interval $(0, 1)$ of a partially ordered ring $R$, the value of $x$ is strictly less than $1$.
Set.Ioo.coe_mul theorem
(x y : Ioo (0 : R) 1) : ↑(x * y) = (x * y : R)
Full source
@[simp, norm_cast]
theorem coe_mul (x y : Ioo (0 : R) 1) : ↑(x * y) = (x * y : R) :=
  rfl
Multiplication in Open Unit Interval Preserves Coefficients
Informal description
For any elements $x$ and $y$ in the open unit interval $(0,1)$ of a partially ordered ring $R$, the product $x * y$ in the interval equals the product $x * y$ in $R$.
Set.Ioo.semigroup instance
: Semigroup (Ioo (0 : R) 1)
Full source
instance semigroup : Semigroup (Ioo (0 : R) 1) := fast_instance%
  Subtype.coe_injective.semigroup _ coe_mul
Semigroup Structure on the Open Unit Interval
Informal description
For any strictly ordered semiring $R$, the open interval $(0,1)$ in $R$ forms a semigroup under multiplication inherited from $R$.
Set.Ioo.commSemigroup instance
{R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] : CommSemigroup (Ioo (0 : R) 1)
Full source
instance commSemigroup {R : Type*} [CommSemiring R] [PartialOrder R] [IsStrictOrderedRing R] :
    CommSemigroup (Ioo (0 : R) 1) := fast_instance%
  Subtype.coe_injective.commSemigroup _ coe_mul
Commutative Semigroup Structure on the Open Unit Interval
Informal description
For any commutative semiring $R$ with a partial order and strict ordered ring structure, the open interval $(0,1)$ in $R$ forms a commutative semigroup under multiplication inherited from $R$.
Set.Ioo.one_sub_mem theorem
{t : β} (ht : t ∈ Ioo (0 : β) 1) : 1 - t ∈ Ioo (0 : β) 1
Full source
theorem one_sub_mem {t : β} (ht : t ∈ Ioo (0 : β) 1) : 1 - t ∈ Ioo (0 : β) 1 := by
  rw [mem_Ioo] at *
  refine ⟨sub_pos.2 ht.2, ?_⟩
  exact lt_of_le_of_ne ((sub_le_self_iff 1).2 ht.1.le) (mt sub_eq_self.mp ht.1.ne')
Closure of Open Unit Interval under One Minus Operation
Informal description
For any element $t$ in the open interval $(0,1)$ of an ordered semiring $\beta$, the element $1 - t$ also lies in $(0,1)$.
Set.Ioo.mem_iff_one_sub_mem theorem
{t : β} : t ∈ Ioo (0 : β) 1 ↔ 1 - t ∈ Ioo (0 : β) 1
Full source
theorem mem_iff_one_sub_mem {t : β} : t ∈ Ioo (0 : β) 1t ∈ Ioo (0 : β) 1 ↔ 1 - t ∈ Ioo (0 : β) 1 :=
  ⟨one_sub_mem, fun h => sub_sub_cancel 1 t ▸ one_sub_mem h⟩
Characterization of Elements in Open Unit Interval via One Minus Operation
Informal description
For any element $t$ in an ordered semiring $\beta$, $t$ belongs to the open interval $(0,1)$ if and only if $1 - t$ also belongs to $(0,1)$. In other words, $0 < t < 1 \leftrightarrow 0 < 1 - t < 1$.
Set.Ioo.one_minus_pos theorem
(x : Ioo (0 : β) 1) : 0 < 1 - (x : β)
Full source
theorem one_minus_pos (x : Ioo (0 : β) 1) : 0 < 1 - (x : β) := by simpa using x.2.2
Positivity of One Minus Element in Open Unit Interval
Informal description
For any element $x$ in the open interval $(0,1)$ of an ordered semiring $\beta$, the difference $1 - x$ is positive, i.e., $0 < 1 - x$.
Set.Ioo.one_minus_lt_one theorem
(x : Ioo (0 : β) 1) : 1 - (x : β) < 1
Full source
theorem one_minus_lt_one (x : Ioo (0 : β) 1) : 1 - (x : β) < 1 := by simpa using x.2.1
Subtraction from One in Open Unit Interval is Less Than One
Informal description
For any element $x$ in the open interval $(0,1)$ of an ordered semiring $\beta$, we have $1 - x < 1$.