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\documentclass{article}
\usepackage{open-axiom}
\begin{document}
\title{\$SPAD/src/algebra laurent.spad}
\author{Clifton J. Williamson, Bill Burge}
\maketitle
\begin{abstract}
\end{abstract}
\eject
\tableofcontents
\eject
\section{category ULSCCAT UnivariateLaurentSeriesConstructorCategory}
<<category ULSCCAT UnivariateLaurentSeriesConstructorCategory>>=
)abbrev category ULSCCAT UnivariateLaurentSeriesConstructorCategory
++ Author: Clifton J. Williamson
++ Date Created: 6 February 1990
++ Date Last Updated: June 18, 2010
++ Basic Operations:
++ Related Domains:
++ Also See:
++ AMS Classifications:
++ Keywords: series, Laurent, Taylor
++ Examples:
++ References:
++ Description:
++   This is a category of univariate Laurent series constructed from
++   univariate Taylor series.  A Laurent series is represented by a pair
++   \spad{[n,f(x)]}, where n is an arbitrary integer and \spad{f(x)}
++   is a Taylor series.  This pair represents the Laurent series
++   \spad{x**n * f(x)}.
UnivariateLaurentSeriesConstructorCategory(Coef,UTS):_
 Category == Definition where
  Coef: Ring
  UTS : UnivariateTaylorSeriesCategory Coef
  I ==> Integer

  Definition ==> Join(UnivariateLaurentSeriesCategory(Coef),_
                      RetractableTo UTS, CoercibleFrom UTS) with
    laurent: (I,UTS) -> %
      ++ \spad{laurent(n,f(x))} returns \spad{x**n * f(x)}.
    degree: % -> I
      ++ \spad{degree(f(x))} returns the degree of the lowest order term of
      ++ \spad{f(x)}, which may have zero as a coefficient.
    taylorRep: % -> UTS
      ++ \spad{taylorRep(f(x))} returns \spad{g(x)}, where
      ++ \spad{f = x**n * g(x)} is represented by \spad{[n,g(x)]}.
    removeZeroes: % -> %
      ++ \spad{removeZeroes(f(x))} removes leading zeroes from the
      ++ representation of the Laurent series \spad{f(x)}.
      ++ A Laurent series is represented by (1) an exponent and
      ++ (2) a Taylor series which may have leading zero coefficients.
      ++ When the Taylor series has a leading zero coefficient, the
      ++ 'leading zero' is removed from the Laurent series as follows:
      ++ the series is rewritten by increasing the exponent by 1 and
      ++ dividing the Taylor series by its variable.
      ++ Note: \spad{removeZeroes(f)} removes all leading zeroes from f
    removeZeroes: (I,%) -> %
      ++ \spad{removeZeroes(n,f(x))} removes up to n leading zeroes from
      ++ the Laurent series \spad{f(x)}.
      ++ A Laurent series is represented by (1) an exponent and
      ++ (2) a Taylor series which may have leading zero coefficients.
      ++ When the Taylor series has a leading zero coefficient, the
      ++ 'leading zero' is removed from the Laurent series as follows:
      ++ the series is rewritten by increasing the exponent by 1 and
      ++ dividing the Taylor series by its variable.
    taylor: % -> UTS
      ++ taylor(f(x)) converts the Laurent series f(x) to a Taylor series,
      ++ if possible.  Error: if this is not possible.
    taylorIfCan: % -> Union(UTS,"failed")
      ++ \spad{taylorIfCan(f(x))} converts the Laurent series \spad{f(x)}
      ++ to a Taylor series, if possible. If this is not possible,
      ++ "failed" is returned.
    if Coef has Field then QuotientFieldCategory(UTS)
      --++ the quotient field of univariate Taylor series over a field is
      --++ the field of Laurent series

   add

    zero? x == zero? taylorRep x
    retract(x:%):UTS == taylor x
    retractIfCan(x:%):Union(UTS,"failed") == taylorIfCan x

@
\section{domain ULSCONS UnivariateLaurentSeriesConstructor}
<<domain ULSCONS UnivariateLaurentSeriesConstructor>>=
)abbrev domain ULSCONS UnivariateLaurentSeriesConstructor
++ Authors: Bill Burge, Clifton J. Williamson
++ Date Created: August 1988
++ Date Last Updated: 17 June 1996
++ Fix History:
++ 14 June 1996: provided missing exquo: (%,%) -> % (Frederic Lehobey)
++ Basic Operations:
++ Related Domains:
++ Also See:
++ AMS Classifications:
++ Keywords: series, Laurent, Taylor
++ Examples:
++ References:
++ Description:
++   This package enables one to construct a univariate Laurent series
++   domain from a univariate Taylor series domain. Univariate
++   Laurent series are represented by a pair \spad{[n,f(x)]}, where n is
++   an arbitrary integer and \spad{f(x)} is a Taylor series.  This pair
++   represents the Laurent series \spad{x**n * f(x)}.
UnivariateLaurentSeriesConstructor(Coef,UTS):_
 Exports == Implementation where
  Coef    : Ring
  UTS     : UnivariateTaylorSeriesCategory Coef
  I     ==> Integer
  L     ==> List
  NNI   ==> NonNegativeInteger
  OUT   ==> OutputForm
  P     ==> Polynomial Coef
  RF    ==> Fraction Polynomial Coef
  RN    ==> Fraction Integer
  ST    ==> Stream Coef
  TERM  ==> Record(k:I,c:Coef)
  monom ==> monomial$UTS
  EFULS ==> ElementaryFunctionsUnivariateLaurentSeries(Coef,UTS,%)
  STTAYLOR ==> StreamTaylorSeriesOperations Coef

  Exports ==> UnivariateLaurentSeriesConstructorCategory(Coef,UTS)

  Implementation ==> add

--% representation

    Rep := Record(expon:I,ps:UTS)

    getExpon : % -> I
    getUTS   : % -> UTS

    getExpon x == x.expon
    getUTS   x == x.ps

--% creation and destruction

    laurent(n,psr) == [n,psr]
    taylorRep x    == getUTS x
    degree x       == getExpon x

    0 == laurent(0,0)
    1 == laurent(0,1)

    monomial(s,e) == laurent(e,s::UTS)

    coerce(uts:UTS):% == laurent(0,uts)
    coerce(r:Coef):%  == r :: UTS  :: %
    coerce(i:I):%     == i :: Coef :: %

    taylorIfCan uls ==
      n := getExpon uls
      negative? n =>
        uls := removeZeroes(-n,uls)
        negative? getExpon(uls) => "failed"
        getUTS uls
      n = 0 => getUTS uls
      getUTS(uls) * monom(1,n :: NNI)

    taylor uls ==
      (uts := taylorIfCan uls) case "failed" =>
        error "taylor: Laurent series has a pole"
      uts :: UTS

    termExpon: TERM -> I
    termExpon term == term.k
    termCoef: TERM -> Coef
    termCoef term == term.c
    rec: (I,Coef) -> TERM
    rec(exponent,coef) == [exponent,coef]

    recs: (ST,I) -> Stream TERM
    recs(st,n) == delay
      empty? st => empty()
      zero? (coef := frst st) => recs(rst st,n + 1)
      concat(rec(n,coef),recs(rst st,n + 1))

    terms x == recs(coefficients getUTS x,getExpon x)

    recsToCoefs: (Stream TERM,I) -> ST
    recsToCoefs(st,n) == delay
      empty? st => empty()
      term := frst st; ex := termExpon term
      n = ex => concat(termCoef term,recsToCoefs(rst st,n + 1))
      concat(0,recsToCoefs(rst st,n + 1))

    series st ==
      empty? st => 0
      ex := termExpon frst st
      laurent(ex,series recsToCoefs(st,ex))

--% normalizations

    removeZeroes x ==
      empty? coefficients(xUTS := getUTS x) => 0
      coefficient(xUTS,0) = 0 =>
        removeZeroes laurent(getExpon(x) + 1,quoByVar xUTS)
      x

    removeZeroes(n,x) ==
      n <= 0 => x
      empty? coefficients(xUTS := getUTS x) => 0
      coefficient(xUTS,0) = 0 =>
        removeZeroes(n - 1,laurent(getExpon(x) + 1,quoByVar xUTS))
      x

--% predicates

    x = y ==
      %peq(x,y)$Foreign(Builtin) => true
      (expDiff := getExpon(x) - getExpon(y)) = 0 =>
        getUTS(x) = getUTS(y)
      abs(expDiff) > _$streamCount$Lisp => false
      positive? expDiff =>
        getUTS(x) * monom(1,expDiff :: NNI) = getUTS(y)
      getUTS(y) * monom(1,(- expDiff) :: NNI) = getUTS(x)

    pole? x ==
      (n := degree x) >= 0 => false
      x := removeZeroes(-n,x)
      negative? degree x

--% arithmetic

    x + y  ==
      n := getExpon(x) - getExpon(y)
      n >= 0 =>
        laurent(getExpon y,getUTS(y) + getUTS(x) * monom(1,n::NNI))
      laurent(getExpon x,getUTS(x) + getUTS(y) * monom(1,(-n)::NNI))

    x - y  ==
      n := getExpon(x) - getExpon(y)
      n >= 0 =>
        laurent(getExpon y,getUTS(x) * monom(1,n::NNI) - getUTS(y))
      laurent(getExpon x,getUTS(x) - getUTS(y) * monom(1,(-n)::NNI))

    x:% * y:% == laurent(getExpon x + getExpon y,getUTS x * getUTS y)

    x:% ** n:NNI ==
      zero? n =>
        zero? x => error "0 ** 0 is undefined"
        1
      laurent(n * getExpon(x),getUTS(x) ** n)

    recip x ==
      x := removeZeroes(1000,x)
      zero? coefficient(x,d := degree x) => "failed"
      (uts := recip getUTS x) case "failed" => "failed"
      laurent(-d,uts :: UTS)

    elt(uls1:%,uls2:%) ==
      (uts := taylorIfCan uls2) case "failed" =>
        error "elt: second argument must have positive order"
      uts2 := uts :: UTS
      not zero? coefficient(uts2,0) =>
        error "elt: second argument must have positive order"
      if negative?(deg := getExpon uls1) then uls1 := removeZeroes(-deg,uls1)
      negative?(deg := getExpon uls1) =>
        (recipr := recip(uts2 :: %)) case "failed" =>
          error "elt: second argument not invertible"
        uts1 := taylor(uls1 * monomial(1,-deg))
        (elt(uts1,uts2) :: %) * (recipr :: %) ** ((-deg) :: NNI)
      elt(taylor uls1,uts2) :: %

    eval(uls:%,r:Coef) ==
      if negative?(n := getExpon uls) then uls := removeZeroes(-n,uls)
      uts := getUTS uls
      negative?(n := getExpon uls) =>
        zero? r => error "eval: 0 raised to negative power"
        (recipr := recip r) case "failed" =>
          error "eval: non-unit raised to negative power"
        (recipr :: Coef) ** ((-n) :: NNI) *$STTAYLOR eval(uts,r)
      zero? n => eval(uts,r)
      r ** (n :: NNI) *$STTAYLOR eval(uts,r)

--% values

    variable x == variable getUTS x
    center   x == center   getUTS x

    coefficient(x,n) ==
      a := n - getExpon(x)
      a >= 0 => coefficient(getUTS x,a :: NNI)
      0

    elt(x:%,n:I) == coefficient(x,n)

--% other functions

    order x == getExpon x + order getUTS x
    order(x,n) ==
      negative?(m := n - (e := getExpon x)) => n
      e + order(getUTS x,m :: NNI)

    truncate(x,n) ==
      negative?(m := n - (e := getExpon x)) => 0
      laurent(e,truncate(getUTS x,m :: NNI))

    truncate(x,n1,n2) ==
      if n2 < n1 then (n1,n2) := (n2,n1)
      negative?(m1 := n1 - (e := getExpon x)) => truncate(x,n2)
      laurent(e,truncate(getUTS x,m1 :: NNI,(n2 - e) :: NNI))

    if Coef has IntegralDomain then
      rationalFunction(x,n) ==
        negative?(m := n - (e := getExpon x)) => 0
        poly := polynomial(getUTS x,m :: NNI) :: RF
        zero? e => poly
        v := variable(x) :: RF; c := center(x) :: P :: RF
        positive? e => poly * (v - c) ** (e :: NNI)
        poly / (v - c) ** ((-e) :: NNI)

      rationalFunction(x,n1,n2) ==
        if n2 < n1 then (n1,n2) := (n2,n1)
        negative?(m1 := n1 - (e := getExpon x)) => rationalFunction(x,n2)
        poly := polynomial(getUTS x,m1 :: NNI,(n2 - e) :: NNI) :: RF
        zero? e => poly
        v := variable(x) :: RF; c := center(x) :: P :: RF
        positive? e => poly * (v - c) ** (e :: NNI)
        poly / (v - c) ** ((-e) :: NNI)

      --  La fonction < exquo > manque dans laurent.spad,
      --les lignes suivantes le mettent en evidence : 
      --
      --ls := laurent(0,series [i for i in 1..])$ULS(INT,x,0)
      ---- missing function in laurent.spad of Axiom 2.0a version of
      ---- Friday March 10, 1995 at 04:15:22 on 615:
      --exquo(ls,ls)
      --
      --  Je l'ai ajoutee a laurent.spad.
      --
      --Frederic Lehobey
      x exquo y ==
        x := removeZeroes(1000,x)
	y := removeZeroes(1000,y)
	zero? coefficient(y, d := degree y) => "failed"
	(uts := (getUTS x) exquo (getUTS y)) case "failed" => "failed"
	laurent(degree x-d,uts :: UTS)

    if Coef has coerce: Symbol -> Coef then
      if Coef has "**": (Coef,I) -> Coef then

        approximate(x,n) ==
          negative?(m := n - (e := getExpon x)) => 0
          app := approximate(getUTS x,m :: NNI)
          zero? e => app
          app * ((variable(x) :: Coef) - center(x)) ** e

    complete x == laurent(getExpon x,complete getUTS x)
    extend(x,n) ==
      e := getExpon x
      negative?(m := n - e) => x
      laurent(e,extend(getUTS x,m :: NNI))

    map(f:Coef -> Coef,x:%) == laurent(getExpon x,map(f,getUTS x))

    multiplyCoefficients(f,x) ==
      e := getExpon x
      laurent(e,multiplyCoefficients(f(e + #1),getUTS x))

    multiplyExponents(x,n) ==
      laurent(n * getExpon x,multiplyExponents(getUTS x,n))

    differentiate x ==
      e := getExpon x
      laurent(e - 1,multiplyCoefficients((e + #1) :: Coef,getUTS x))

    if Coef has PartialDifferentialRing(Symbol) then
      differentiate(x:%,s:Symbol) ==
        (s = variable(x)) => differentiate x
        map(differentiate(#1,s),x) - differentiate(center x,s)*differentiate(x)

    characteristic == characteristic$Coef

    if Coef has Field then

      retract(x:%):UTS                      == taylor x
      retractIfCan(x:%):Union(UTS,"failed") == taylorIfCan x

      (x:%) ** (n:I) ==
        zero? n =>
          zero? x => error "0 ** 0 is undefined"
          1
        positive? n => laurent(n * getExpon(x),getUTS(x) ** (n :: NNI))
        xInv := inv x; minusN := (-n) :: NNI
        laurent(minusN * getExpon(xInv),getUTS(xInv) ** minusN)

      (x:UTS) * (y:%) == (x :: %) * y
      (x:%) * (y:UTS) == x * (y :: %)

      inv x ==
        (xInv := recip x) case "failed" =>
          error "multiplicative inverse does not exist"
        xInv :: %

      (x:%) / (y:%) ==
        (yInv := recip y) case "failed" =>
          error "inv: multiplicative inverse does not exist"
        x * (yInv :: %)

      (x:UTS) / (y:UTS) == (x :: %) / (y :: %)

      numer x ==
        (n := degree x) >= 0 => taylor x
        x := removeZeroes(-n,x)
        (n := degree x) = 0 => taylor x
        getUTS x

      denom x ==
        (n := degree x) >= 0 => 1
        x := removeZeroes(-n,x)
        (n := degree x) = 0 => 1
        monom(1,(-n) :: NNI)

--% algebraic and transcendental functions

    if Coef has Algebra Fraction Integer then

      coerce(r:RN) == r :: Coef :: %

      if Coef has Field then
         (x:%) ** (r:RN) == x **$EFULS r

      exp x   == exp(x)$EFULS
      log x   == log(x)$EFULS
      sin x   == sin(x)$EFULS
      cos x   == cos(x)$EFULS
      tan x   == tan(x)$EFULS
      cot x   == cot(x)$EFULS
      sec x   == sec(x)$EFULS
      csc x   == csc(x)$EFULS
      asin x  == asin(x)$EFULS
      acos x  == acos(x)$EFULS
      atan x  == atan(x)$EFULS
      acot x  == acot(x)$EFULS
      asec x  == asec(x)$EFULS
      acsc x  == acsc(x)$EFULS
      sinh x  == sinh(x)$EFULS
      cosh x  == cosh(x)$EFULS
      tanh x  == tanh(x)$EFULS
      coth x  == coth(x)$EFULS
      sech x  == sech(x)$EFULS
      csch x  == csch(x)$EFULS
      asinh x == asinh(x)$EFULS
      acosh x == acosh(x)$EFULS
      atanh x == atanh(x)$EFULS
      acoth x == acoth(x)$EFULS
      asech x == asech(x)$EFULS
      acsch x == acsch(x)$EFULS

      ratInv: I -> Coef
      ratInv n ==
        zero? n => 1
        inv(n :: RN) :: Coef

      integrate x ==
        not zero? coefficient(x,-1) =>
          error "integrate: series has term of order -1"
        e := getExpon x
        laurent(e + 1,multiplyCoefficients(ratInv(e + 1 + #1),getUTS x))

      if Coef has integrate: (Coef,Symbol) -> Coef and _
         Coef has variables: Coef -> List Symbol then
        integrate(x:%,s:Symbol) ==
          (s = variable(x)) => integrate x
          not entry?(s,variables center x) => map(integrate(#1,s),x)
          error "integrate: center is a function of variable of integration"

      if Coef has TranscendentalFunctionCategory and _
         Coef has PrimitiveFunctionCategory and _
         Coef has AlgebraicallyClosedFunctionSpace Integer then

        integrateWithOneAnswer: (Coef,Symbol) -> Coef
        integrateWithOneAnswer(f,s) ==
          res := integrate(f,s)$FunctionSpaceIntegration(I,Coef)
          res case Coef => res :: Coef
          first(res :: List Coef)

        integrate(x:%,s:Symbol) ==
          (s = variable(x)) => integrate x
          not entry?(s,variables center x) =>
            map(integrateWithOneAnswer(#1,s),x)
          error "integrate: center is a function of variable of integration"

    termOutput:(I,Coef,OUT) -> OUT
    termOutput(k,c,vv) ==
    -- creates a term c * vv ** k
      k = 0 => c :: OUT
      mon :=
        k = 1 => vv
        vv ** (k :: OUT)
      c = 1 => mon
      c = -1 => -mon
      (c :: OUT) * mon

    showAll?:() -> Boolean
    -- check a global Lisp variable
    showAll?() == true

    termsToOutputForm:(I,ST,OUT) -> OUT
    termsToOutputForm(m,uu,xxx) ==
      l : L OUT := empty()
      empty? uu => (0$Coef) :: OUT
      count : NNI := _$streamCount$Lisp
      n : NNI := 0
      while n <= count and not empty? uu repeat
        if frst(uu) ~= 0 then
          l := concat(termOutput((n :: I) + m,frst(uu),xxx),l)
        uu := rst uu
        n := n + 1
      if showAll?() then
        n := count + 1
        while explicitEntries? uu and _
               not eq?(uu,rst uu) repeat
          if frst(uu) ~= 0 then
            l := concat(termOutput((n::I) + m,frst(uu),xxx),l)
          uu := rst uu
          n := n + 1
      l :=
        explicitlyEmpty? uu => l
        eq?(uu,rst uu) and frst uu = 0 => l
        concat(prefix("O" :: OUT,[xxx ** ((n :: I) + m) :: OUT]),l)
      empty? l => (0$Coef) :: OUT
      reduce("+",reverse! l)

    coerce(x:%):OUT ==
      x := removeZeroes(_$streamCount$Lisp,x)
      m := degree x
      uts := getUTS x
      p := coefficients uts
      var := variable uts; cen := center uts
      xxx :=
        zero? cen => var :: OUT
        paren(var :: OUT - cen :: OUT)
      termsToOutputForm(m,p,xxx)

@
\section{domain ULS UnivariateLaurentSeries}
<<domain ULS UnivariateLaurentSeries>>=
)abbrev domain ULS UnivariateLaurentSeries
++ Author: Clifton J. Williamson
++ Date Created: 18 January 1990
++ Date Last Updated: 21 September 1993
++ Basic Operations:
++ Related Domains:
++ Also See:
++ AMS Classifications:
++ Keywords: series, Laurent
++ Examples:
++ References:
++ Description: Dense Laurent series in one variable
++   \spadtype{UnivariateLaurentSeries} is a domain representing Laurent
++   series in one variable with coefficients in an arbitrary ring.  The
++   parameters of the type specify the coefficient ring, the power series
++   variable, and the center of the power series expansion.  For example,
++   \spad{UnivariateLaurentSeries(Integer,x,3)} represents Laurent series in
++   \spad{(x - 3)} with integer coefficients.
UnivariateLaurentSeries(Coef,var,cen): Exports == Implementation where
  Coef : Ring
  var  : Symbol
  cen  : Coef
  I   ==> Integer
  UTS ==> UnivariateTaylorSeries(Coef,var,cen)

  Exports ==> Join(UnivariateLaurentSeriesConstructorCategory(Coef,UTS),_
                   PartialDifferentialDomain(%,Variable var)) with
    coerce: Variable(var) -> %
      ++ \spad{coerce(var)} converts the series variable \spad{var} into a
      ++ Laurent series.
    if Coef has Algebra Fraction Integer then
      integrate: (%,Variable(var)) -> %
        ++ \spad{integrate(f(x))} returns an anti-derivative of the power
        ++ series \spad{f(x)} with constant coefficient 0.
        ++ We may integrate a series when we can divide coefficients
        ++ by integers.

  Implementation ==> UnivariateLaurentSeriesConstructor(Coef,UTS) add

    variable x == var
    center   x == cen

    coerce(v:Variable(var)) ==
      zero? cen => monomial(1,1)
      monomial(1,1) + monomial(cen,0)

    differentiate(x:%,v:Variable(var)) == differentiate x

    if Coef has Algebra Fraction Integer then
      integrate(x:%,v:Variable(var)) == integrate x

@
\section{package ULS2 UnivariateLaurentSeriesFunctions2}
<<package ULS2 UnivariateLaurentSeriesFunctions2>>=
)abbrev package ULS2 UnivariateLaurentSeriesFunctions2
++ Author: Clifton J. Williamson
++ Date Created: 5 March 1990
++ Date Last Updated: 5 March 1990
++ Basic Operations:
++ Related Domains:
++ Also See:
++ AMS Classifications:
++ Keywords: Laurent series, map
++ Examples:
++ References:
++ Description: Mapping package for univariate Laurent series
++   This package allows one to apply a function to the coefficients of
++   a univariate Laurent series.
UnivariateLaurentSeriesFunctions2(Coef1,Coef2,var1,var2,cen1,cen2):_
 Exports == Implementation where
  Coef1 : Ring
  Coef2 : Ring
  var1: Symbol
  var2: Symbol
  cen1: Coef1
  cen2: Coef2
  ULS1  ==> UnivariateLaurentSeries(Coef1, var1, cen1)
  ULS2  ==> UnivariateLaurentSeries(Coef2, var2, cen2)
  UTS1  ==> UnivariateTaylorSeries(Coef1, var1, cen1)
  UTS2  ==> UnivariateTaylorSeries(Coef2, var2, cen2)
  UTSF2 ==> UnivariateTaylorSeriesFunctions2(Coef1, Coef2, UTS1, UTS2)

  Exports ==> with
    map: (Coef1 -> Coef2,ULS1) -> ULS2
      ++ \spad{map(f,g(x))} applies the map f to the coefficients of the Laurent
      ++ series \spad{g(x)}.

  Implementation ==> add

    map(f,ups) == laurent(degree ups, map(f, taylorRep ups)$UTSF2)

@
\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>>

<<category ULSCCAT UnivariateLaurentSeriesConstructorCategory>>
<<domain ULSCONS UnivariateLaurentSeriesConstructor>>
<<domain ULS UnivariateLaurentSeries>>
<<package ULS2 UnivariateLaurentSeriesFunctions2>>
@
\eject
\begin{thebibliography}{99}
\bibitem{1} nothing
\end{thebibliography}
\end{document}