Initial population.

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+\documentclass{article}
+\usepackage{axiom}
+\begin{document}
+\title{\$SPAD/src/algebra pdecomp.spad}
+\author{The Axiom Team}
+\maketitle
+\begin{abstract}
+\end{abstract}
+\eject
+\tableofcontents
+\eject
+\section{package PCOMP PolynomialComposition}
+<<package PCOMP PolynomialComposition>>=
+)abbrev package PCOMP PolynomialComposition
+++ Description:
+++ This package \undocumented
+PolynomialComposition(UP: UnivariatePolynomialCategory(R), R: Ring): with
+        compose: (UP, UP) -> UP
+		++ compose(p,q) \undocumented
+    == add
+        compose(g, h) ==
+            r: UP := 0
+            while g ^= 0 repeat
+                r := leadingCoefficient(g)*h**degree(g) + r
+                g := reductum g
+            r
+
+@
+\section{package PDECOMP PolynomialDecomposition}
+<<package PDECOMP PolynomialDecomposition>>=
+)abbrev package PDECOMP PolynomialDecomposition
+++ Description:
+++ This package \undocumented
+--  Ref: Kozen and Landau, Cornell University  TR 86-773
+PolynomialDecomposition(UP, F): PDcat == PDdef where
+    F:Field
+    UP:UnivariatePolynomialCategory F
+    NNI ==> NonNegativeInteger
+    LR  ==> Record(left: UP, right: UP)
+ 
+    PDcat == with
+        decompose: UP -> List UP
+		++ decompose(up) \undocumented
+        decompose: (UP, NNI, NNI) -> Union(LR, "failed")
+		++ decompose(up,m,n) \undocumented
+        leftFactor: (UP, UP) -> Union(UP, "failed") 
+		++ leftFactor(p,q) \undocumented
+        rightFactorCandidate:  (UP, NNI) -> UP
+		++ rightFactorCandidate(p,n) \undocumented
+    PDdef == add
+        leftFactor(f, h) ==
+             g: UP := 0
+             for i in 0.. while f ^= 0 repeat
+                 fr := divide(f, h)
+                 f := fr.quotient; r := fr.remainder
+                 degree r > 0 => return "failed"
+                 g := g + r * monomial(1, i)
+             g
+ 
+        decompose(f, dg, dh) ==
+            df := degree f
+            dg*dh ^= df => "failed"
+            h := rightFactorCandidate(f, dh)
+            g := leftFactor(f, h)
+            g case "failed" => "failed"
+            [g::UP, h]
+ 
+        decompose f ==
+            df := degree f
+            for dh in 2..df-1 | df rem dh = 0 repeat
+                h := rightFactorCandidate(f, dh)
+                g := leftFactor(f, h)
+                g case UP => return
+                    append(decompose(g::UP), decompose h)
+            [f]
+        rightFactorCandidate(f, dh) ==
+            f  := f/leadingCoefficient f
+            df := degree f
+            dg := df quo dh
+            h  := monomial(1, dh)
+            for k in 1..dh repeat
+                hdg:= h**dg
+                c  := (coefficient(f,(df-k)::NNI)-coefficient(hdg,(df-k)::NNI))/(dg::F)
+                h  := h + monomial(c, (dh-k)::NNI)
+            h - monomial(coefficient(h, 0), 0) -- drop constant term
+
+@
+\section{License}
+<<license>>=
+--Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
+--All rights reserved.
+--
+--Redistribution and use in source and binary forms, with or without
+--modification, are permitted provided that the following conditions are
+--met:
+--
+--    - Redistributions of source code must retain the above copyright
+--      notice, this list of conditions and the following disclaimer.
+--
+--    - Redistributions in binary form must reproduce the above copyright
+--      notice, this list of conditions and the following disclaimer in
+--      the documentation and/or other materials provided with the
+--      distribution.
+--
+--    - Neither the name of The Numerical ALgorithms Group Ltd. nor the
+--      names of its contributors may be used to endorse or promote products
+--      derived from this software without specific prior written permission.
+--
+--THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+--IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+--TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+--PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+--OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+--EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+--PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+--PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+--LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+--NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+--SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+@
+<<*>>=
+<<license>>
+ 
+--% Polynomial composition and decomposition functions
+--  If f = g o h then  g = leftFactor(f, h)  &  h = rightFactor(f, g)
+--  SMW Dec 86
+
+<<package PCOMP PolynomialComposition>>
+<<package PDECOMP PolynomialDecomposition>>
+@
+\eject
+\begin{thebibliography}{99}
+\bibitem{1} nothing
+\end{thebibliography}
+\end{document}