path: root/src/algebra/expr.spad.pamphlet

\documentclass{article}
\usepackage{axiom}
\begin{document}
\title{\$SPAD/src/algebra expr.spad}
\author{Manuel Bronstein, Barry Trager}
\maketitle
\begin{abstract}
\end{abstract}
\eject
\tableofcontents
\eject
\section{domain EXPR Expression}
<<domain EXPR Expression>>=
)abbrev domain EXPR Expression
++ Top-level mathematical expressions
++ Author: Manuel Bronstein
++ Date Created: 19 July 1988
++ Date Last Updated: October 1993 (P.Gianni), February 1995 (MB)
++ Description: Expressions involving symbolic functions.
++ Keywords: operator, kernel, function.
Expression(R:OrderedSet): Exports == Implementation where
  Q   ==> Fraction Integer
  K   ==> Kernel %
  MP  ==> SparseMultivariatePolynomial(R, K)
  AF  ==> AlgebraicFunction(R, %)
  EF  ==> ElementaryFunction(R, %)
  CF  ==> CombinatorialFunction(R, %)
  LF  ==> LiouvillianFunction(R, %)
  AN  ==> AlgebraicNumber
  KAN ==> Kernel AN
  FSF ==> FunctionalSpecialFunction(R, %)
  ESD ==> ExpressionSpace_&(%)
  FSD ==> FunctionSpace_&(%, R)
  SYMBOL ==> "%symbol"
  ALGOP  ==> "%alg"
  POWER  ==> '%power
  SUP    ==> SparseUnivariatePolynomial

  Exports ==> FunctionSpace R with
    if R has IntegralDomain then
      AlgebraicallyClosedFunctionSpace R
      TranscendentalFunctionCategory
      CombinatorialOpsCategory
      LiouvillianFunctionCategory
      SpecialFunctionCategory
      reduce: % -> %
        ++ reduce(f) simplifies all the unreduced algebraic quantities
        ++ present in f by applying their defining relations.
      number?: % -> Boolean
	++ number?(f) tests if f is rational
      simplifyPower: (%,Integer) -> %
	++ simplifyPower?(f,n) \undocumented{}
      if R has GcdDomain then
        factorPolynomial : SUP  % -> Factored SUP %
	   ++ factorPolynomial(p) \undocumented{}
        squareFreePolynomial : SUP % -> Factored SUP %
	   ++ squareFreePolynomial(p) \undocumented{}
      if R has RetractableTo Integer then RetractableTo AN

  Implementation ==> add
    import KernelFunctions2(R, %)

    retNotUnit     : % -> R
    retNotUnitIfCan: % -> Union(R, "failed")

    belong? op == true

    retNotUnit x ==
      (u := constantIfCan(k := retract(x)@K)) case R => u::R
      error "Not retractable"

    retNotUnitIfCan x ==
      (r := retractIfCan(x)@Union(K,"failed")) case "failed" => "failed"
      constantIfCan(r::K)

    if R has IntegralDomain then
      reduc  : (%, List Kernel %) -> %
      commonk   : (%, %) -> List K
      commonk0  : (List K, List K) -> List K
      toprat    : % -> %
      algkernels: List K -> List K
      evl       : (MP, K, SparseUnivariatePolynomial %) -> Fraction MP
      evl0      : (MP, K) -> SparseUnivariatePolynomial Fraction MP

      Rep := Fraction MP
      0                == 0$Rep
      1                == 1$Rep
      one? x           == one?(x)$Rep
      zero? x          == zero?(x)$Rep
      - x:%            == -$Rep x
      n:Integer * x:%  == n *$Rep x
      coerce(n:Integer) ==  coerce(n)$Rep@Rep::%
      x:% * y:%        == reduc(x *$Rep y, commonk(x, y))
      x:% + y:%        == reduc(x +$Rep y, commonk(x, y))
      (x:% - y:%):%    == reduc(x -$Rep y, commonk(x, y))
      x:% / y:%        == reduc(x /$Rep y, commonk(x, y))

      number?(x:%):Boolean ==
        if R has RetractableTo(Integer) then
          ground?(x) or ((retractIfCan(x)@Union(Q,"failed")) case Q)
        else
          ground?(x)

      simplifyPower(x:%,n:Integer):% ==
        k : List K := kernels x
        is?(x,POWER) =>
          -- Look for a power of a number in case we can do a simplification
          args : List % := argument first k
          not(#args = 2) => error "Too many arguments to **"
          number?(args.1) =>
             reduc((args.1) **$Rep n, algkernels kernels (args.1))**(args.2)
          (first args)**(n*second(args))
        reduc(x **$Rep n, algkernels k)

      x:% ** n:NonNegativeInteger ==
        n = 0 => 1$%
        n = 1 => x
        simplifyPower(numerator x,n pretend Integer) / simplifyPower(denominator x,n pretend Integer)

      x:% ** n:Integer ==
        n = 0 => 1$%
        n = 1 => x
        n = -1 => 1/x
        simplifyPower(numerator x,n) / simplifyPower(denominator x,n)

      x:% ** n:PositiveInteger == 
        n = 1 => x
        simplifyPower(numerator x,n pretend Integer) / simplifyPower(denominator x,n pretend Integer)

      x:% < y:%        == x <$Rep y
      x:% = y:%        == x =$Rep y
      numer x          == numer(x)$Rep
      denom x          == denom(x)$Rep
      coerce(p:MP):%   == coerce(p)$Rep
      reduce x         == reduc(x, algkernels kernels x)
      commonk(x, y)    == commonk0(algkernels kernels x, algkernels kernels y)
      algkernels l     == select_!(has?(operator #1, ALGOP), l)
      toprat f == ratDenom(f, algkernels kernels f)$AlgebraicManipulations(R, %)

      x:MP / y:MP ==
        reduc(x /$Rep y,commonk0(algkernels variables x,algkernels variables y))

-- since we use the reduction from FRAC SMP which asssumes that the
-- variables are independent, we must remove algebraic from the denominators
      reducedSystem(m:Matrix %):Matrix(R) ==
        mm:Matrix(MP) := reducedSystem(map(toprat, m))$Rep
        reducedSystem(mm)$MP

-- since we use the reduction from FRAC SMP which asssumes that the
-- variables are independent, we must remove algebraic from the denominators
      reducedSystem(m:Matrix %, v:Vector %):
       Record(mat:Matrix R, vec:Vector R) ==
        r:Record(mat:Matrix MP, vec:Vector MP) :=
          reducedSystem(map(toprat, m), map(toprat, v))$Rep
        reducedSystem(r.mat, r.vec)$MP

-- The result MUST be left sorted deepest first   MB 3/90
      commonk0(x, y) ==
        ans := empty()$List(K)
        for k in reverse_! x repeat if member?(k, y) then ans := concat(k, ans)
        ans

      rootOf(x:SparseUnivariatePolynomial %, v:Symbol) == rootOf(x,v)$AF
      pi()                      == pi()$EF
      exp x                     == exp(x)$EF
      log x                     == log(x)$EF
      sin x                     == sin(x)$EF
      cos x                     == cos(x)$EF
      tan x                     == tan(x)$EF
      cot x                     == cot(x)$EF
      sec x                     == sec(x)$EF
      csc x                     == csc(x)$EF
      asin x                    == asin(x)$EF
      acos x                    == acos(x)$EF
      atan x                    == atan(x)$EF
      acot x                    == acot(x)$EF
      asec x                    == asec(x)$EF
      acsc x                    == acsc(x)$EF
      sinh x                    == sinh(x)$EF
      cosh x                    == cosh(x)$EF
      tanh x                    == tanh(x)$EF
      coth x                    == coth(x)$EF
      sech x                    == sech(x)$EF
      csch x                    == csch(x)$EF
      asinh x                   == asinh(x)$EF
      acosh x                   == acosh(x)$EF
      atanh x                   == atanh(x)$EF
      acoth x                   == acoth(x)$EF
      asech x                   == asech(x)$EF
      acsch x                   == acsch(x)$EF

      abs x                     == abs(x)$FSF
      Gamma x                   == Gamma(x)$FSF
      Gamma(a, x)               == Gamma(a, x)$FSF
      Beta(x,y)                 == Beta(x,y)$FSF
      digamma x                 == digamma(x)$FSF
      polygamma(k,x)            == polygamma(k,x)$FSF
      besselJ(v,x)              == besselJ(v,x)$FSF
      besselY(v,x)              == besselY(v,x)$FSF
      besselI(v,x)              == besselI(v,x)$FSF
      besselK(v,x)              == besselK(v,x)$FSF
      airyAi x                  == airyAi(x)$FSF
      airyBi x                  == airyBi(x)$FSF

      x:% ** y:%                == x **$CF y
      factorial x               == factorial(x)$CF
      binomial(n, m)            == binomial(n, m)$CF
      permutation(n, m)         == permutation(n, m)$CF
      factorials x              == factorials(x)$CF
      factorials(x, n)          == factorials(x, n)$CF
      summation(x:%, n:Symbol)           == summation(x, n)$CF
      summation(x:%, s:SegmentBinding %) == summation(x, s)$CF
      product(x:%, n:Symbol)             == product(x, n)$CF
      product(x:%, s:SegmentBinding %)   == product(x, s)$CF

      erf x                              == erf(x)$LF
      Ei x                               == Ei(x)$LF
      Si x                               == Si(x)$LF
      Ci x                               == Ci(x)$LF
      li x                               == li(x)$LF
      dilog x                            == dilog(x)$LF
      integral(x:%, n:Symbol)            == integral(x, n)$LF
      integral(x:%, s:SegmentBinding %)  == integral(x, s)$LF

      operator op ==
        belong?(op)$AF  => operator(op)$AF
        belong?(op)$EF  => operator(op)$EF
        belong?(op)$CF  => operator(op)$CF
        belong?(op)$LF  => operator(op)$LF
        belong?(op)$FSF => operator(op)$FSF
        belong?(op)$FSD => operator(op)$FSD
        belong?(op)$ESD => operator(op)$ESD
        nullary? op and has?(op, SYMBOL) => operator(kernel(name op)$K)
        operator(name op, arity op)

      reduc(x, l) ==
        for k in l repeat
          p := minPoly k
          x := evl(numer x, k, p) /$Rep evl(denom x, k, p)
        x

      evl0(p, k) ==
        numer univariate(p::Fraction(MP),
                     k)$PolynomialCategoryQuotientFunctions(IndexedExponents K,
                                                            K,R,MP,Fraction MP)

      -- uses some operations from Rep instead of % in order not to
      -- reduce recursively during those operations.
      evl(p, k, m) ==
        degree(p, k) < degree m => p::Fraction(MP)
        (((evl0(p, k) pretend SparseUnivariatePolynomial($)) rem m)
           pretend SparseUnivariatePolynomial Fraction MP) (k::MP::Fraction(MP))

      if R has GcdDomain then
        noalg?: SUP % -> Boolean

        noalg? p ==
          while p ~= 0 repeat
            not empty? algkernels kernels leadingCoefficient p => return false
            p := reductum p
          true

        gcdPolynomial(p:SUP %, q:SUP %) ==
          noalg? p and noalg? q => gcdPolynomial(p, q)$Rep
          gcdPolynomial(p, q)$GcdDomain_&(%)

        factorPolynomial(x:SUP %) : Factored SUP % ==
          uf:= factor(x pretend SUP(Rep))$SupFractionFactorizer(
                                          IndexedExponents K,K,R,MP)
          uf pretend Factored SUP %

        squareFreePolynomial(x:SUP %) : Factored SUP % ==
          uf:= squareFree(x pretend SUP(Rep))$SupFractionFactorizer(
                                          IndexedExponents K,K,R,MP)
          uf pretend Factored SUP %

      if R is AN then
        -- this is to force the coercion R -> EXPR R to be used
        -- instead of the coercioon AN -> EXPR R which loops.
        -- simpler looking code will fail! MB 10/91
        coerce(x:AN):% == (monomial(x, 0$IndexedExponents(K))$MP)::%

      if (R has RetractableTo Integer) then
        x:% ** r:Q                           == x **$AF r
        minPoly k                            == minPoly(k)$AF
        definingPolynomial x                 == definingPolynomial(x)$AF
        retract(x:%):Q                       == retract(x)$Rep
        retractIfCan(x:%):Union(Q, "failed") == retractIfCan(x)$Rep

        if not(R is AN) then
          k2expr  : KAN -> %
          smp2expr: SparseMultivariatePolynomial(Integer, KAN) -> %
          R2AN    : R  -> Union(AN, "failed")
          k2an    : K  -> Union(AN, "failed")
          smp2an  : MP -> Union(AN, "failed")


          coerce(x:AN):% == smp2expr(numer x) / smp2expr(denom x)
          k2expr k       == map(#1::%, k)$ExpressionSpaceFunctions2(AN, %)

          smp2expr p ==
            map(k2expr,#1::%,p)$PolynomialCategoryLifting(IndexedExponents KAN,
                   KAN, Integer, SparseMultivariatePolynomial(Integer, KAN), %)

          retractIfCan(x:%):Union(AN, "failed") ==
            ((n:= smp2an numer x) case AN) and ((d:= smp2an denom x) case AN)
                 => (n::AN) / (d::AN)
            "failed"

          R2AN r ==
            (u := retractIfCan(r::%)@Union(Q, "failed")) case Q => u::Q::AN
            "failed"

          k2an k ==
            not(belong?(op := operator k)$AN) => "failed"
            arg:List(AN) := empty()
            for x in argument k repeat
              if (a := retractIfCan(x)@Union(AN, "failed")) case "failed" then
                return "failed"
              else arg := concat(a::AN, arg)
            (operator(op)$AN) reverse_!(arg)

          smp2an p ==
            (x1 := mainVariable p) case "failed" => R2AN leadingCoefficient p
            up := univariate(p, k := x1::K)
            (t  := k2an k) case "failed" => "failed"
            ans:AN := 0
            while not ground? up repeat
              (c:=smp2an leadingCoefficient up) case "failed" => return "failed"
              ans := ans + (c::AN) * (t::AN) ** (degree up)
              up  := reductum up
            (c := smp2an leadingCoefficient up) case "failed" => "failed"
            ans + c::AN

      if R has ConvertibleTo InputForm then
        convert(x:%):InputForm == convert(x)$Rep
        import MakeUnaryCompiledFunction(%, %, %)
        eval(f:%, op: BasicOperator, g:%, x:Symbol):% == 
          eval(f,[op],[g],x)
        eval(f:%, ls:List BasicOperator, lg:List %, x:Symbol) ==
	  -- handle subsrcipted symbols by renaming -> eval -> renaming back
          llsym:List List Symbol:=[variables g for g in lg]
          lsym:List Symbol:= removeDuplicates concat llsym
          lsd:List Symbol:=select (scripted?,lsym)
          empty? lsd=> eval(f,ls,[compiledFunction(g, x) for g in lg])
          ns:List Symbol:=[new()$Symbol for i in lsd]
          lforwardSubs:List Equation % := [(i::%)= (j::%) for i in lsd for j in ns]
          lbackwardSubs:List Equation % := [(j::%)= (i::%) for i in lsd for j in ns]
          nlg:List % :=[subst(g,lforwardSubs) for g in lg]
          res:% :=eval(f, ls, [compiledFunction(g, x) for g in nlg])
          subst(res,lbackwardSubs)
      if R has PatternMatchable Integer then
        patternMatch(x:%, p:Pattern Integer,
         l:PatternMatchResult(Integer, %)) ==
          patternMatch(x, p, l)$PatternMatchFunctionSpace(Integer, R, %)

      if R has PatternMatchable Float then
        patternMatch(x:%, p:Pattern Float,
         l:PatternMatchResult(Float, %)) ==
          patternMatch(x, p, l)$PatternMatchFunctionSpace(Float, R, %)

    else  -- R is not an integral domain
      operator op ==
        belong?(op)$FSD => operator(op)$FSD
        belong?(op)$ESD => operator(op)$ESD
        nullary? op and has?(op, SYMBOL) => operator(kernel(name op)$K)
        operator(name op, arity op)

      if R has Ring then
        Rep := MP
        0              == 0$Rep
        1              == 1$Rep
        - x:%          == -$Rep x
        n:Integer *x:% == n *$Rep x
        x:% * y:%      == x *$Rep y
        x:% + y:%      == x +$Rep y
        x:% = y:%      == x =$Rep y
        x:% < y:%      == x <$Rep y
        numer x        == x@Rep
        coerce(p:MP):% == p

        reducedSystem(m:Matrix %):Matrix(R) ==
          reducedSystem(m)$Rep

        reducedSystem(m:Matrix %, v:Vector %):
         Record(mat:Matrix R, vec:Vector R) ==
          reducedSystem(m, v)$Rep

        if R has ConvertibleTo InputForm then
          convert(x:%):InputForm == convert(x)$Rep

        if R has PatternMatchable Integer then
          kintmatch: (K,Pattern Integer,PatternMatchResult(Integer,Rep))
                                     -> PatternMatchResult(Integer, Rep)

          kintmatch(k, p, l) ==
            patternMatch(k, p, l pretend PatternMatchResult(Integer, %)
              )$PatternMatchKernel(Integer, %)
                pretend PatternMatchResult(Integer, Rep)

          patternMatch(x:%, p:Pattern Integer,
           l:PatternMatchResult(Integer, %)) ==
            patternMatch(x@Rep, p,
                         l pretend PatternMatchResult(Integer, Rep),
                          kintmatch
                           )$PatternMatchPolynomialCategory(Integer,
                            IndexedExponents K, K, R, Rep)
                              pretend PatternMatchResult(Integer, %)

        if R has PatternMatchable Float then
          kfltmatch: (K, Pattern Float, PatternMatchResult(Float, Rep))
                                     -> PatternMatchResult(Float, Rep)

          kfltmatch(k, p, l) ==
            patternMatch(k, p, l pretend PatternMatchResult(Float, %)
              )$PatternMatchKernel(Float, %)
                pretend PatternMatchResult(Float, Rep)

          patternMatch(x:%, p:Pattern Float,
           l:PatternMatchResult(Float, %)) ==
            patternMatch(x@Rep, p,
                         l pretend PatternMatchResult(Float, Rep),
                          kfltmatch
                           )$PatternMatchPolynomialCategory(Float,
                            IndexedExponents K, K, R, Rep)
                              pretend PatternMatchResult(Float, %)

      else   -- R is not even a ring
        if R has AbelianMonoid then
          import ListToMap(K, %)

          kereval        : (K, List K, List %) -> %
          subeval        : (K, List K, List %) -> %

          Rep := FreeAbelianGroup K

          0              == 0$Rep
          x:% + y:%      == x +$Rep y
          x:% = y:%      == x =$Rep y
          x:% < y:%      == x <$Rep y
          coerce(k:K):%  == coerce(k)$Rep
          kernels x      == [f.gen for f in terms x]
          coerce(x:R):%  == (zero? x => 0; constantKernel(x)::%)
          retract(x:%):R == (zero? x => 0; retNotUnit x)
          coerce(x:%):OutputForm == coerce(x)$Rep
          kereval(k, lk, lv) == match(lk, lv, k, map(eval(#1, lk, lv), #1))

          subeval(k, lk, lv) ==
            match(lk, lv, k,
              kernel(operator #1, [subst(a, lk, lv) for a in argument #1]))

          isPlus x ==
            empty?(l := terms x) or empty? rest l => "failed"
            [t.exp *$Rep t.gen for t in l]$List(%)

          isMult x ==
            empty?(l := terms x) or not empty? rest l => "failed"
            t := first l
            [t.exp, t.gen]

          eval(x:%, lk:List K, lv:List %) ==
            _+/[t.exp * kereval(t.gen, lk, lv) for t in terms x]

          subst(x:%, lk:List K, lv:List %) ==
            _+/[t.exp * subeval(t.gen, lk, lv) for t in terms x]

          retractIfCan(x:%):Union(R, "failed") ==
            zero? x => 0
            retNotUnitIfCan x

          if R has AbelianGroup then -(x:%) == -$Rep x

--      else      -- R is not an AbelianMonoid
--        if R has SemiGroup then
--    Rep := FreeGroup K
--    1              == 1$Rep
--    x:% * y:%      == x *$Rep y
--    x:% = y:%      == x =$Rep y
--    coerce(k:K):%  == k::Rep
--    kernels x      == [f.gen for f in factors x]
--    coerce(x:R):%  == (one? x => 1; constantKernel x)
--    retract(x:%):R == (one? x => 1; retNotUnit x)
--    coerce(x:%):OutputForm == coerce(x)$Rep

--    retractIfCan(x:%):Union(R, "failed") ==
--      one? x => 1
--      retNotUnitIfCan x

--    if R has Group then inv(x:%):% == inv(x)$Rep

        else   -- R is nothing
            import ListToMap(K, %)

            Rep := K

            x:% < y:%      == x <$Rep y
            x:% = y:%      == x =$Rep y
            coerce(k:K):%  == k
            kernels x      == [x pretend K]
            coerce(x:R):%  == constantKernel x
            retract(x:%):R == retNotUnit x
            retractIfCan(x:%):Union(R, "failed") == retNotUnitIfCan x
            coerce(x:%):OutputForm               == coerce(x)$Rep

            eval(x:%, lk:List K, lv:List %) ==
              match(lk, lv, x pretend K, map(eval(#1, lk, lv), #1))

            subst(x, lk, lv) ==
              match(lk, lv, x pretend K,
                kernel(operator #1, [subst(a, lk, lv) for a in argument #1]))

            if R has ConvertibleTo InputForm then
              convert(x:%):InputForm == convert(x)$Rep

--          if R has PatternMatchable Integer then
--            convert(x:%):Pattern(Integer) == convert(x)$Rep
--
--            patternMatch(x:%, p:Pattern Integer,
--             l:PatternMatchResult(Integer, %)) ==
--              patternMatch(x pretend K,p,l)$PatternMatchKernel(Integer, %)
--
--          if R has PatternMatchable Float then
--            convert(x:%):Pattern(Float) == convert(x)$Rep
--
--            patternMatch(x:%, p:Pattern Float,
--             l:PatternMatchResult(Float, %)) ==
--              patternMatch(x pretend K, p, l)$PatternMatchKernel(Float, %)

@
\section{package PAN2EXPR PolynomialAN2Expression}
<<package PAN2EXPR PolynomialAN2Expression>>=
)abbrev package PAN2EXPR PolynomialAN2Expression
++ Author: Barry Trager
++ Date Created: 8 Oct 1991
++ Description: This package provides a coerce from polynomials over
++ algebraic numbers to \spadtype{Expression AlgebraicNumber}.
PolynomialAN2Expression():Target == Implementation where
  EXPR ==> Expression(Integer)
  AN ==> AlgebraicNumber
  PAN ==> Polynomial AN
  SY ==> Symbol
  Target ==> with
      coerce: Polynomial AlgebraicNumber -> Expression(Integer)
        ++ coerce(p) converts the polynomial \spad{p} with algebraic number
        ++ coefficients to \spadtype{Expression Integer}.
      coerce: Fraction Polynomial AlgebraicNumber -> Expression(Integer)
        ++ coerce(rf) converts \spad{rf}, a fraction of polynomial \spad{p} with
        ++ algebraic number coefficients to \spadtype{Expression Integer}.
  Implementation ==> add
    coerce(p:PAN):EXPR ==
        map(#1::EXPR, #1::EXPR, p)$PolynomialCategoryLifting(
                                  IndexedExponents SY, SY, AN, PAN, EXPR)
    coerce(rf:Fraction PAN):EXPR ==
        numer(rf)::EXPR / denom(rf)::EXPR

@
\section{package EXPR2 ExpressionFunctions2}
<<package EXPR2 ExpressionFunctions2>>=
)abbrev package EXPR2 ExpressionFunctions2
++ Lifting of maps to Expressions
++ Author: Manuel Bronstein
++ Description: Lifting of maps to Expressions.
++ Date Created: 16 Jan 1989
++ Date Last Updated: 22 Jan 1990
ExpressionFunctions2(R:OrderedSet, S:OrderedSet):
 Exports == Implementation where
  K   ==> Kernel R
  F2  ==> FunctionSpaceFunctions2(R, Expression R, S, Expression S)
  E2  ==> ExpressionSpaceFunctions2(Expression R, Expression S)

  Exports ==> with
    map: (R -> S, Expression R) -> Expression S
      ++ map(f, e) applies f to all the constants appearing in e.

  Implementation == add
    if S has Ring and R has Ring then
      map(f, r) == map(f, r)$F2
    else
      map(f, r) == map(map(f, #1), retract r)$E2

@
\section{package PMPREDFS FunctionSpaceAttachPredicates}
<<package PMPREDFS FunctionSpaceAttachPredicates>>=
)abbrev package PMPREDFS FunctionSpaceAttachPredicates
++ Predicates for pattern-matching.
++ Author: Manuel Bronstein
++ Description: Attaching predicates to symbols for pattern matching.
++ Date Created: 21 Mar 1989
++ Date Last Updated: 23 May 1990
++ Keywords: pattern, matching.
FunctionSpaceAttachPredicates(R, F, D): Exports == Implementation where
  R: OrderedSet
  F: FunctionSpace R
  D: Type

  K  ==> Kernel F

  Exports ==> with
    suchThat: (F, D -> Boolean) -> F
      ++ suchThat(x, foo) attaches the predicate foo to x;
      ++ error if x is not a symbol.
    suchThat: (F, List(D -> Boolean)) -> F
      ++ suchThat(x, [f1, f2, ..., fn]) attaches the predicate
      ++ f1 and f2 and ... and fn to x.
      ++ Error: if x is not a symbol.

  Implementation ==> add
    macro PMPRED  == '%pmpredicate
    import AnyFunctions1(D -> Boolean)

    st   : (K, List Any) -> F
    preds: K -> List Any
    mkk  : BasicOperator -> F

    suchThat(p:F, f:D -> Boolean) == suchThat(p, [f])
    mkk op                        == kernel(op, empty()$List(F))

    preds k ==
      (u := property(operator k, PMPRED)) case nothing => empty()
      (u@None) pretend List(Any)

    st(k, l) ==
      mkk assert(setProperty(copy operator k, PMPRED,
                 concat(preds k, l) pretend None), string(new()$Symbol))

    suchThat(p:F, l:List(D -> Boolean)) ==
      retractIfCan(p)@Union(Symbol, "failed") case Symbol =>
        st(retract(p)@K, [f::Any for f in l])
      error "suchThat must be applied to symbols only"

@
\section{package PMASSFS FunctionSpaceAssertions}
<<package PMASSFS FunctionSpaceAssertions>>=
)abbrev package PMASSFS FunctionSpaceAssertions
++ Assertions for pattern-matching
++ Author: Manuel Bronstein
++ Description: Attaching assertions to symbols for pattern matching;
++ Date Created: 21 Mar 1989
++ Date Last Updated: 23 May 1990
++ Keywords: pattern, matching.
FunctionSpaceAssertions(R, F): Exports == Implementation where
  R: OrderedSet
  F: FunctionSpace R

  K  ==> Kernel F

  Exports ==> with
    assert  : (F, Identifier) -> F
      ++ assert(x, s) makes the assertion s about x.
      ++ Error: if x is not a symbol.
    constant: F -> F
      ++ constant(x) tells the pattern matcher that x should
      ++ match only the symbol 'x and no other quantity.
      ++ Error: if x is not a symbol.
    optional: F -> F
      ++ optional(x) tells the pattern matcher that x can match
      ++ an identity (0 in a sum, 1 in a product or exponentiation).
      ++ Error: if x is not a symbol.
    multiple: F -> F
      ++ multiple(x) tells the pattern matcher that x should
      ++ preferably match a multi-term quantity in a sum or product.
      ++ For matching on lists, multiple(x) tells the pattern matcher
      ++ that x should match a list instead of an element of a list.
      ++ Error: if x is not a symbol.

  Implementation ==> add
    macro PMOPT == '%pmoptional
    macro PMMULT == '%pmmultiple
    macro PMCONST == '%pmconstant
    mkk  : BasicOperator -> F

    mkk op == kernel(op, empty()$List(F))

    ass(k: K, s: Identifier): F ==
      has?(op := operator k, s) => k::F
      mkk assert(copy op, s)

    asst(k: K, s: Identifier): F ==
      has?(op := operator k, s) => k::F
      mkk assert(op, s)

    assert(x, s) ==
      retractIfCan(x)@Union(Symbol, "failed") case Symbol =>
        asst(retract(x)@K, s)
      error "assert must be applied to symbols only"

    constant x ==
      retractIfCan(x)@Union(Symbol, "failed") case Symbol =>
        ass(retract(x)@K, PMCONST)
      error "constant must be applied to symbols only"

    optional x ==
      retractIfCan(x)@Union(Symbol, "failed") case Symbol =>
        ass(retract(x)@K, PMOPT)
      error "optional must be applied to symbols only"

    multiple x ==
      retractIfCan(x)@Union(Symbol, "failed") case Symbol =>
        ass(retract(x)@K, PMMULT)
      error "multiple must be applied to symbols only"

@
\section{package PMPRED AttachPredicates}
<<package PMPRED AttachPredicates>>=
)abbrev package PMPRED AttachPredicates
++ Predicates for pattern-matching
++ Author: Manuel Bronstein
++ Description: Attaching predicates to symbols for pattern matching.
++ Date Created: 21 Mar 1989
++ Date Last Updated: 23 May 1990
++ Keywords: pattern, matching.
AttachPredicates(D:Type): Exports == Implementation where
  FE ==> Expression Integer

  Exports ==> with
    suchThat: (Symbol, D -> Boolean) -> FE
      ++ suchThat(x, foo) attaches the predicate foo to x.
    suchThat: (Symbol, List(D -> Boolean)) -> FE
      ++ suchThat(x, [f1, f2, ..., fn]) attaches the predicate
      ++ f1 and f2 and ... and fn to x.

  Implementation ==> add
    import FunctionSpaceAttachPredicates(Integer, FE, D)

    suchThat(p:Symbol, f:D -> Boolean)       == suchThat(p::FE, f)
    suchThat(p:Symbol, l:List(D -> Boolean)) == suchThat(p::FE, l)

@
\section{package PMASS PatternMatchAssertions}
<<package PMASS PatternMatchAssertions>>=
)abbrev package PMASS PatternMatchAssertions
++ Assertions for pattern-matching
++ Author: Manuel Bronstein
++ Description: Attaching assertions to symbols for pattern matching.
++ Date Created: 21 Mar 1989
++ Date Last Updated: 23 May 1990
++ Keywords: pattern, matching.
PatternMatchAssertions(): Exports == Implementation where
  FE ==> Expression Integer

  Exports ==> with
    assert  : (Symbol, String) -> FE
      ++ assert(x, s) makes the assertion s about x.
    constant: Symbol -> FE
      ++ constant(x) tells the pattern matcher that x should
      ++ match only the symbol 'x and no other quantity.
    optional: Symbol -> FE
      ++ optional(x) tells the pattern matcher that x can match
      ++ an identity (0 in a sum, 1 in a product or exponentiation).;
    multiple: Symbol -> FE
      ++ multiple(x) tells the pattern matcher that x should
      ++ preferably match a multi-term quantity in a sum or product.
      ++ For matching on lists, multiple(x) tells the pattern matcher
      ++ that x should match a list instead of an element of a list.

  Implementation ==> add
    import FunctionSpaceAssertions(Integer, FE)

    constant x   == constant(x::FE)
    multiple x   == multiple(x::FE)
    optional x   == optional(x::FE)
    assert(x, s) == assert(x::FE, s)

@
\section{domain HACKPI Pi}
<<domain HACKPI Pi>>=
)abbrev domain HACKPI Pi
++ Expressions in %pi only
++ Author: Manuel Bronstein
++ Description:
++  Symbolic fractions in %pi with integer coefficients;
++  The point for using Pi as the default domain for those fractions
++  is that Pi is coercible to the float types, and not Expression.
++ Date Created: 21 Feb 1990
++ Date Last Updated: 12 Mai 1992
Pi(): Exports == Implementation where
  PZ ==> Polynomial Integer
  UP ==> SparseUnivariatePolynomial Integer
  RF ==> Fraction UP

  Exports ==> Join(Field, CharacteristicZero, RetractableTo Integer,
                   RetractableTo Fraction Integer, RealConstant,
                   CoercibleTo DoubleFloat, CoercibleTo Float,
                   ConvertibleTo RF, ConvertibleTo InputForm) with
    pi: () -> % ++ pi() returns the symbolic %pi.
  Implementation ==> RF add
    Rep := RF

    sympi := '%pi

    p2sf: UP -> DoubleFloat
    p2f : UP -> Float
    p2o : UP -> OutputForm
    p2i : UP -> InputForm
    p2p:  UP -> PZ

    pi()                    == (monomial(1, 1)$UP :: RF) pretend %
    convert(x:%):RF         == x pretend RF
    convert(x:%):Float      == x::Float
    convert(x:%):DoubleFloat == x::DoubleFloat
    coerce(x:%):DoubleFloat  == p2sf(numer x) / p2sf(denom x)
    coerce(x:%):Float       == p2f(numer x) / p2f(denom x)
    p2o p                   == outputForm(p, sympi::OutputForm)
    p2i p                   == convert p2p p

    p2p p ==
      ans:PZ := 0
      while p ~= 0 repeat
        ans := ans + monomial(leadingCoefficient(p)::PZ, sympi, degree p)
        p   := reductum p
      ans

    coerce(x:%):OutputForm ==
      (r := retractIfCan(x)@Union(UP, "failed")) case UP => p2o(r::UP)
      p2o(numer x) / p2o(denom x)

    convert(x:%):InputForm ==
      (r := retractIfCan(x)@Union(UP, "failed")) case UP => p2i(r::UP)
      p2i(numer x) / p2i(denom x)

    p2sf p ==
      map(#1::DoubleFloat, p)$SparseUnivariatePolynomialFunctions2(
        Integer, DoubleFloat) (pi()$DoubleFloat)

    p2f p ==
      map(#1::Float, p)$SparseUnivariatePolynomialFunctions2(
        Integer, Float) (pi()$Float)

@
\section{package PICOERCE PiCoercions}
<<package PICOERCE PiCoercions>>=
)abbrev package PICOERCE PiCoercions
++ Coercions from %pi to symbolic or numeric domains
++ Author: Manuel Bronstein
++ Description:
++  Provides a coercion from the symbolic fractions in %pi with
++ integer coefficients to any Expression type.
++ Date Created: 21 Feb 1990
++ Date Last Updated: 21 Feb 1990
PiCoercions(R:Join(OrderedSet, IntegralDomain)): with
  coerce: Pi -> Expression R
    ++ coerce(f) returns f as an Expression(R).
 == add
  p2e: SparseUnivariatePolynomial Integer -> Expression R

  coerce(x:Pi):Expression(R) ==
    f := convert(x)@Fraction(SparseUnivariatePolynomial Integer)
    p2e(numer f) / p2e(denom f)

  p2e p ==
    map(#1::Expression(R), p)$SparseUnivariatePolynomialFunctions2(
        Integer, Expression R) (pi()$Expression(R))

@
\section{License}
<<license>>=
--Copyright (c) 1991-2002, The Numerical ALgorithms Group Ltd.
--All rights reserved.
--Copyright (C) 2007-2009, Gabriel Dos Reis.
--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>>

-- SPAD files for the functional world should be compiled in the
-- following order:
--
--   op  kl  fspace  algfunc elemntry combfunc EXPR

<<domain EXPR Expression>>
<<package PAN2EXPR PolynomialAN2Expression>>
<<package EXPR2 ExpressionFunctions2>>
<<package PMPREDFS FunctionSpaceAttachPredicates>>
<<package PMASSFS FunctionSpaceAssertions>>
<<package PMPRED AttachPredicates>>
<<package PMASS PatternMatchAssertions>>
<<domain HACKPI Pi>>
<<package PICOERCE PiCoercions>>
@
\eject
\begin{thebibliography}{99}
\bibitem{1} nothing
\end{thebibliography}
\end{document}