Rotate #
This file adds the ability to rotate triangles and triangle morphisms. It also shows that rotation gives an equivalence on the category of triangles.
If you rotate a triangle, you get another triangle. Given a triangle of the form:
f g h
X ───> Y ───> Z ───> X⟦1⟧
applying rotate
gives a triangle of the form:
g h -f⟦1⟧'
Y ───> Z ───> X⟦1⟧ ───> Y⟦1⟧
Equations
- CategoryTheory.Pretriangulated.Triangle.rotate T = CategoryTheory.Pretriangulated.Triangle.mk T.mor₂ T.mor₃ (-(CategoryTheory.shiftFunctor C 1).toPrefunctor.map T.mor₁)
Instances For
Given a triangle of the form:
f g h
X ───> Y ───> Z ───> X⟦1⟧
applying invRotate
gives a triangle that can be thought of as:
-h⟦-1⟧' f g
Z⟦-1⟧ ───> X ───> Y ───> Z
(note that this diagram doesn't technically fit the definition of triangle, as Z⟦-1⟧⟦1⟧
is
not necessarily equal to Z
, but it is isomorphic, by the counitIso
of shiftEquiv C 1
)
Equations
- One or more equations did not get rendered due to their size.
Instances For
Rotating triangles gives an endofunctor on the category of triangles in C
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The inverse rotation of triangles gives an endofunctor on the category of triangles in C
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The unit isomorphism of the auto-equivalence of categories triangleRotation C
of
Triangle C
given by the rotation of triangles.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The counit isomorphism of the auto-equivalence of categories triangleRotation C
of
Triangle C
given by the rotation of triangles.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Rotating triangles gives an auto-equivalence on the category of triangles in C
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Equations
- CategoryTheory.Pretriangulated.instIsEquivalenceTriangleTriangleCategoryRotate = let_fun this := inferInstance; this
Equations
- CategoryTheory.Pretriangulated.instIsEquivalenceTriangleTriangleCategoryInvRotate = let_fun this := inferInstance; this