Complementary embeddings #
Given two embeddings e₁ : c₁.Embedding c
and e₂ : c₂.Embedding c
of complex shapes, we introduce a property e₁.AreComplementary e₂
saying that the image subsets of the indices of c₁
and c₂
form
a partition of the indices of c
.
If e₁.IsTruncLE
and e₂.IsTruncGE
, and K : HomologicalComplex C c
,
we construct a quasi-isomorphism shortComplexTruncLEX₃ToTruncGE
between
the cokernel of K.ιTruncLE e₁ : K.truncLE e₁ ⟶ K
and K.truncGE e₂
.
Two embedding e₁
and e₂
into a complex shape c : ComplexShape ι
are complementary when the range of e₁.f
and e₂.f
form a partition of ι
.
Instances For
Given complementary embeddings of complex shapes
e₁ : Embedding c₁ c
and e₂ : Embedding c₂ c
, this is
the obvious map ι₁ ⊕ ι₂ → ι
from the sum of the index
types of c₁
and c₂
to the index type of c
.
Equations
Instances For
Given complementary embeddings of complex shapes
e₁ : Embedding c₁ c
and e₂ : Embedding c₂ c
, this is
the obvious bijection ι₁ ⊕ ι₂ ≃ ι
from the sum of the index
types of c₁
and c₂
to the index type of c
.
Equations
Instances For
Auxiliary definition for desc
.
Equations
Instances For
If ι₁
and ι₂
are the index types of complementary embeddings into a
complex shape of index type ι
, this is a constructor for (dependent) maps from ι
,
which takes as inputs the "restrictions" to ι₁
and ι₂
.
Equations
Instances For
Variant of hom_ext
.
If e₁
and e₂
are complementary embeddings into a complex shape c
,
indices i₁
and i₂
are at the boundary if c.Rel (e₁.f i₁) (e₂.f i₂)
.
Equations
Instances For
If ac : AreComplementary e₁ e₂
(with e₁ : ComplexShape.Embedding c₁ c
and
e₂ : ComplexShape.Embedding c₂ c
), and i₁
belongs to e₁.BoundaryLE
,
then this is the (unique) index i₂
of c₂
such that ac.Boundary i₁ i₂
.
Equations
Instances For
If ac : AreComplementary e₁ e₂
(with e₁ : ComplexShape.Embedding c₁ c
and
e₂ : ComplexShape.Embedding c₂ c
), and i₂
belongs to e₂.BoundaryGE
,
then this is the (unique) index i₁
of c₁
such that ac.Boundary i₁ i₂
.
Equations
Instances For
The bijection Subtype e₁.BoundaryLE ≃ Subtype e₂.BoundaryGE
when
e₁
and e₂
are complementary embeddings of complex shapes.
Equations
Instances For
When e₁
and e₂
are complementary embeddings of complex shapes, with
e₁.IsTruncLE
and e₂.IsTruncGE
, then this is the canonical quasi-isomorphism
(K.shortComplexTruncLE e₁).X₃ ⟶ K.truncGE e₂
where
(K.shortComplexTruncLE e₁).X₃
is the cokernel of K.ιTruncLE e₁ : K.truncLE e₁ ⟶ K
.