Documentation

Mathlib.Topology.ContinuousMap.Defs

Continuous bundled maps #

In this file we define the type ContinuousMap of continuous bundled maps.

We use the DFunLike design, so each type of morphisms has a companion typeclass which is meant to be satisfied by itself and all stricter types.

structure ContinuousMap (X : Type u_1) (Y : Type u_2) [TopologicalSpace X] [TopologicalSpace Y] :
Type (max u_1 u_2)

The type of continuous maps from X to Y.

When possible, instead of parametrizing results over (f : C(X, Y)), you should parametrize over {F : Type*} [ContinuousMapClass F X Y] (f : F).

When you extend this structure, make sure to extend ContinuousMapClass.

  • toFun : X β†’ Y

    The function X β†’ Y

  • continuous_toFun : Continuous self.toFun

    Proposition that toFun is continuous

Instances For

    C(X, Y) is the type of continuous maps from X to Y.

    Equations
      Instances For
        class ContinuousMapClass (F : Type u_1) (X : outParam (Type u_2)) (Y : outParam (Type u_3)) [TopologicalSpace X] [TopologicalSpace Y] [FunLike F X Y] :

        ContinuousMapClass F X Y states that F is a type of continuous maps.

        You should extend this class when you extend ContinuousMap.

        • map_continuous (f : F) : Continuous ⇑f

          Continuity

        Instances
          def toContinuousMap {F : Type u_1} {X : Type u_2} {Y : Type u_3} [TopologicalSpace X] [TopologicalSpace Y] [FunLike F X Y] [ContinuousMapClass F X Y] (f : F) :
          C(X, Y)

          Coerce a bundled morphism with a ContinuousMapClass instance to a ContinuousMap.

          Equations
            Instances For
              instance instCoeTCContinuousMap {F : Type u_1} {X : Type u_2} {Y : Type u_3} [TopologicalSpace X] [TopologicalSpace Y] [FunLike F X Y] [ContinuousMapClass F X Y] :
              CoeTC F C(X, Y)
              Equations

                Continuous maps #

                @[simp]
                theorem ContinuousMap.toFun_eq_coe {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {f : C(X, Y)} :
                f.toFun = ⇑f
                def ContinuousMap.Simps.apply {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) :
                X β†’ Y

                See note [custom simps projection].

                Equations
                  Instances For
                    @[simp]
                    theorem ContinuousMap.coe_coe {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {F : Type u_3} [FunLike F X Y] [ContinuousMapClass F X Y] (f : F) :
                    ⇑↑f = ⇑f
                    theorem ContinuousMap.coe_apply {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {F : Type u_3} [FunLike F X Y] [ContinuousMapClass F X Y] (f : F) (x : X) :
                    ↑f x = f x

                    Coercion to a ContinuousMap is injective.

                    The unprimed version ContinuousMap.coe_injective is used for the coercion from C(X, Y) to X β†’ Y.

                    theorem ContinuousMap.ext {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {f g : C(X, Y)} (h : βˆ€ (a : X), f a = g a) :
                    f = g
                    theorem ContinuousMap.ext_iff {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {f g : C(X, Y)} :
                    f = g ↔ βˆ€ (a : X), f a = g a
                    def ContinuousMap.copy {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) (f' : X β†’ Y) (h : f' = ⇑f) :
                    C(X, Y)

                    Copy of a ContinuousMap with a new toFun equal to the old one. Useful to fix definitional equalities.

                    Equations
                      Instances For
                        @[simp]
                        theorem ContinuousMap.coe_copy {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) (f' : X β†’ Y) (h : f' = ⇑f) :
                        ⇑(f.copy f' h) = f'
                        theorem ContinuousMap.copy_eq {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) (f' : X β†’ Y) (h : f' = ⇑f) :
                        f.copy f' h = f
                        theorem ContinuousMap.continuous {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) :
                        Continuous ⇑f

                        Deprecated. Use map_continuous instead.

                        theorem ContinuousMap.congr_fun {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] {f g : C(X, Y)} (H : f = g) (x : X) :
                        f x = g x

                        Deprecated. Use DFunLike.congr_fun instead.

                        theorem ContinuousMap.congr_arg {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : C(X, Y)) {x y : X} (h : x = y) :
                        f x = f y

                        Deprecated. Use DFunLike.congr_arg instead.

                        @[simp]
                        theorem ContinuousMap.coe_mk {X : Type u_1} {Y : Type u_2} [TopologicalSpace X] [TopologicalSpace Y] (f : X β†’ Y) (h : Continuous f) :
                        ⇑{ toFun := f, continuous_toFun := h } = f