--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+(* This file was automatically generated: do not edit *********************)
+
+set "baseuri" "cic:/matita/CoRN-Decl/ftc/Composition".
+
+include "CoRN.ma".
+
+(* $Id: Composition.v,v 1.4 2004/04/23 10:00:58 lcf Exp $ *)
+
+include "ftc/MoreFunctions.ma".
+
+(* UNEXPORTED
+Section Maps_into_Compacts
+*)
+
+(* UNEXPORTED
+Section Part_Funct
+*)
+
+(*#* *Composition
+
+Preservation results for functional composition are treated in this
+separate file. We start by defining some auxiliary predicates, and
+then prove the preservation of continuity through composition and the
+chain rule for differentiation, both for compact and arbitrary
+intervals.
+
+%\begin{convention}% Throughout this section:
+- [a, b : IR] and [I] will denote [[a,b]];
+- [c, d : IR] and [J] will denote [[c,d]];
+- [F, F', G, G'] will be partial functions.
+
+%\end{convention}%
+
+** Maps into Compacts
+
+Both continuity and differentiability proofs require extra hypothesis
+on the functions involved---namely, that every compact interval is
+mapped into another compact interval. We define this concept for
+partial functions, and prove some trivial results.
+*)
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/F.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/G.var".
+
+alias id "a" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/a.var".
+
+alias id "b" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/b.var".
+
+alias id "Hab" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/Hab.var".
+
+alias id "c" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/c.var".
+
+alias id "d" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/d.var".
+
+alias id "Hcd" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/Hcd.var".
+
+(* begin hide *)
+
+inline "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/I.con" "Maps_into_Compacts__Part_Funct__".
+
+(* end hide *)
+
+(* begin show *)
+
+alias id "Hf" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/Hf.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/maps_into_compacts.con".
+
+(* begin show *)
+
+alias id "maps" = "cic:/CoRN/ftc/Composition/Maps_into_Compacts/Part_Funct/maps.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/maps_lemma'.con".
+
+inline "cic:/CoRN/ftc/Composition/maps_lemma.con".
+
+inline "cic:/CoRN/ftc/Composition/maps_lemma_less.con".
+
+inline "cic:/CoRN/ftc/Composition/maps_lemma_inc.con".
+
+(* UNEXPORTED
+End Part_Funct
+*)
+
+(* UNEXPORTED
+End Maps_into_Compacts
+*)
+
+(* UNEXPORTED
+Section Mapping
+*)
+
+(*#*
+As was the case for division of partial functions, this condition
+completely characterizes the domain of the composite function.
+*)
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Mapping/F.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Mapping/G.var".
+
+alias id "a" = "cic:/CoRN/ftc/Composition/Mapping/a.var".
+
+alias id "b" = "cic:/CoRN/ftc/Composition/Mapping/b.var".
+
+alias id "Hab" = "cic:/CoRN/ftc/Composition/Mapping/Hab.var".
+
+alias id "c" = "cic:/CoRN/ftc/Composition/Mapping/c.var".
+
+alias id "d" = "cic:/CoRN/ftc/Composition/Mapping/d.var".
+
+alias id "Hcd" = "cic:/CoRN/ftc/Composition/Mapping/Hcd.var".
+
+(* begin show *)
+
+alias id "Hf" = "cic:/CoRN/ftc/Composition/Mapping/Hf.var".
+
+alias id "Hg" = "cic:/CoRN/ftc/Composition/Mapping/Hg.var".
+
+alias id "maps" = "cic:/CoRN/ftc/Composition/Mapping/maps.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/included_comp.con".
+
+(* UNEXPORTED
+End Mapping
+*)
+
+(* UNEXPORTED
+Section Interval_Continuity
+*)
+
+(*#* **Continuity
+
+We now prove that the composition of two continuous partial functions is continuous.
+*)
+
+alias id "a" = "cic:/CoRN/ftc/Composition/Interval_Continuity/a.var".
+
+alias id "b" = "cic:/CoRN/ftc/Composition/Interval_Continuity/b.var".
+
+alias id "Hab" = "cic:/CoRN/ftc/Composition/Interval_Continuity/Hab.var".
+
+(* begin hide *)
+
+inline "cic:/CoRN/ftc/Composition/Interval_Continuity/I.con" "Interval_Continuity__".
+
+(* end hide *)
+
+alias id "c" = "cic:/CoRN/ftc/Composition/Interval_Continuity/c.var".
+
+alias id "d" = "cic:/CoRN/ftc/Composition/Interval_Continuity/d.var".
+
+alias id "Hcd" = "cic:/CoRN/ftc/Composition/Interval_Continuity/Hcd.var".
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Interval_Continuity/F.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Interval_Continuity/G.var".
+
+(* begin show *)
+
+alias id "contF" = "cic:/CoRN/ftc/Composition/Interval_Continuity/contF.var".
+
+alias id "contG" = "cic:/CoRN/ftc/Composition/Interval_Continuity/contG.var".
+
+alias id "Hmap" = "cic:/CoRN/ftc/Composition/Interval_Continuity/Hmap.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/Continuous_I_comp.con".
+
+(* UNEXPORTED
+End Interval_Continuity
+*)
+
+(* UNEXPORTED
+Section Derivative
+*)
+
+(*#* **Derivative
+
+We now work with the derivative relation and prove the chain rule for partial functions.
+*)
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Derivative/F.var".
+
+alias id "F'" = "cic:/CoRN/ftc/Composition/Derivative/F'.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Derivative/G.var".
+
+alias id "G'" = "cic:/CoRN/ftc/Composition/Derivative/G'.var".
+
+alias id "a" = "cic:/CoRN/ftc/Composition/Derivative/a.var".
+
+alias id "b" = "cic:/CoRN/ftc/Composition/Derivative/b.var".
+
+alias id "Hab'" = "cic:/CoRN/ftc/Composition/Derivative/Hab'.var".
+
+alias id "c" = "cic:/CoRN/ftc/Composition/Derivative/c.var".
+
+alias id "d" = "cic:/CoRN/ftc/Composition/Derivative/d.var".
+
+alias id "Hcd'" = "cic:/CoRN/ftc/Composition/Derivative/Hcd'.var".
+
+(* begin hide *)
+
+inline "cic:/CoRN/ftc/Composition/Derivative/Hab.con" "Derivative__".
+
+inline "cic:/CoRN/ftc/Composition/Derivative/Hcd.con" "Derivative__".
+
+inline "cic:/CoRN/ftc/Composition/Derivative/I.con" "Derivative__".
+
+(* end hide *)
+
+(* begin show *)
+
+alias id "derF" = "cic:/CoRN/ftc/Composition/Derivative/derF.var".
+
+alias id "derG" = "cic:/CoRN/ftc/Composition/Derivative/derG.var".
+
+alias id "Hmap" = "cic:/CoRN/ftc/Composition/Derivative/Hmap.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/included_comp'.con".
+
+inline "cic:/CoRN/ftc/Composition/maps'.con".
+
+inline "cic:/CoRN/ftc/Composition/Derivative_I_comp.con".
+
+(*#*
+The next lemma will be useful when we move on to differentiability.
+*)
+
+inline "cic:/CoRN/ftc/Composition/Diffble_I_comp_aux.con".
+
+(* UNEXPORTED
+End Derivative
+*)
+
+(* UNEXPORTED
+Section Differentiability
+*)
+
+(*#* **Differentiability
+
+Finally, we move on to differentiability.
+*)
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Differentiability/F.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Differentiability/G.var".
+
+alias id "a" = "cic:/CoRN/ftc/Composition/Differentiability/a.var".
+
+alias id "b" = "cic:/CoRN/ftc/Composition/Differentiability/b.var".
+
+alias id "Hab'" = "cic:/CoRN/ftc/Composition/Differentiability/Hab'.var".
+
+alias id "c" = "cic:/CoRN/ftc/Composition/Differentiability/c.var".
+
+alias id "d" = "cic:/CoRN/ftc/Composition/Differentiability/d.var".
+
+alias id "Hcd'" = "cic:/CoRN/ftc/Composition/Differentiability/Hcd'.var".
+
+(* begin hide *)
+
+inline "cic:/CoRN/ftc/Composition/Differentiability/Hab.con" "Differentiability__".
+
+inline "cic:/CoRN/ftc/Composition/Differentiability/Hcd.con" "Differentiability__".
+
+inline "cic:/CoRN/ftc/Composition/Differentiability/I.con" "Differentiability__".
+
+(* end hide *)
+
+(* begin show *)
+
+alias id "diffF" = "cic:/CoRN/ftc/Composition/Differentiability/diffF.var".
+
+alias id "diffG" = "cic:/CoRN/ftc/Composition/Differentiability/diffG.var".
+
+alias id "Hmap" = "cic:/CoRN/ftc/Composition/Differentiability/Hmap.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/Diffble_I_comp.con".
+
+(* UNEXPORTED
+End Differentiability
+*)
+
+(* UNEXPORTED
+Section Generalized_Intervals
+*)
+
+(*#* **Generalizations
+
+We now generalize this results to arbitrary intervals. We begin by generalizing the notion of mapping compacts into compacts.
+
+%\begin{convention}% We assume [I,J] to be proper intervals.
+%\end{convention}%
+*)
+
+alias id "I" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/I.var".
+
+alias id "J" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/J.var".
+
+alias id "pI" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/pI.var".
+
+alias id "pJ" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/pJ.var".
+
+inline "cic:/CoRN/ftc/Composition/maps_compacts_into.con".
+
+(*#*
+Now everything comes naturally:
+*)
+
+inline "cic:/CoRN/ftc/Composition/comp_inc_lemma.con".
+
+alias id "F" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/F.var".
+
+alias id "F'" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/F'.var".
+
+alias id "G" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/G.var".
+
+alias id "G'" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/G'.var".
+
+(* begin show *)
+
+alias id "Hmap" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/Hmap.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/Continuous_comp.con".
+
+(* begin show *)
+
+alias id "Hmap'" = "cic:/CoRN/ftc/Composition/Generalized_Intervals/Hmap'.var".
+
+(* end show *)
+
+inline "cic:/CoRN/ftc/Composition/Derivative_comp.con".
+
+(* UNEXPORTED
+End Generalized_Intervals
+*)
+
+(* UNEXPORTED
+Section Corollaries
+*)
+
+(*#*
+Finally, some criteria to prove that a function with a specific domain maps compacts into compacts:
+*)
+
+inline "cic:/CoRN/ftc/Composition/positive_fun.con".
+
+inline "cic:/CoRN/ftc/Composition/negative_fun.con".
+
+inline "cic:/CoRN/ftc/Composition/positive_imp_maps_compacts_into.con".
+
+inline "cic:/CoRN/ftc/Composition/negative_imp_maps_compacts_into.con".
+
+inline "cic:/CoRN/ftc/Composition/Continuous_imp_maps_compacts_into.con".
+
+(*#*
+As a corollary, we get the generalization of differentiability property.
+*)
+
+inline "cic:/CoRN/ftc/Composition/Diffble_comp.con".
+
+(* UNEXPORTED
+End Corollaries
+*)
+
+(* UNEXPORTED
+Hint Immediate included_comp: included.
+*)
+
+(* UNEXPORTED
+Hint Immediate Continuous_I_comp Continuous_comp: continuous.
+*)
+
projects / helm.git / blobdiff