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Submitted by : (unknown) at: 2007-11-17T22:29:19-08:00 (10 years ago)
Name :
Axiom Version :
Category : Severity : Status :
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Axiom provides functionality to evaluate operators using a given evaluation function. Unfortunately, it is broken.

axiom
g := operator 'g;
Type: BasicOperator
axiom
eval(g(1783), g, i+->i)

\label{eq1}1783(1)
Type: Expression(Integer)
axiom
eval(g(n), g, i+->i)

\label{eq2}n(2)
Type: Expression(Integer)
axiom
eval(a*g(n), g, i+->i)

\label{eq3}a \  n(3)
Type: Expression(Integer)
axiom
eval(a*g(1783), g, i+->i)

\label{eq4}{1783}\  a(4)
Type: Expression(Integer)

I guess that the problem is in 'smprep$FS':

      smprep(lop, lexp, lfunc, p) ==
      ..(v := mainVariable p) case "failed" => p::%
      ..symbolIfCan(k := v::K) case SY => p::%
      ..g := (op := operator k)
      .....(arg := [eval(a,lop,lexp,lfunc) for a in argument k]$List(%))
      ..q := map(eval(#1::%, lop, lexp, lfunc),
      ...........univariate(p, k))$SparseUnivariatePolynomialFunctions2(MP, %)
      ..(n := position(name op, lop)) < minIndex lop => q g
      ..a:%  := 0
      ..f    := eval((lfunc.n) arg, lop, lexp, lfunc)
      ..e    := lexp.n
      ..while q ^= 0 repeat
      ....m  := degree q
      ....qr := divide(m, e)
      ....t1 := f ** (qr.quotient)::N
      ....t2 := g ** (qr.remainder)::N
      ....a  := a + leadingCoefficient(q) * t1 * t2
      ....q  := reductum q
      ..a

It seems that Axiom picks the wrong mainVariable in the broken case, namely a instead of g(1783). I badly need this fixed...

Martin

Status: open => fix proposed

Status: fix proposed => fixed somewhere

no patch available

From wh-sandbox --alfredo, Thu, 28 Aug 2008 18:49:01 -0700 reply
http://axiom.svn.sourceforge.net/viewvc/axiom/branches/wh-sandbox/src/algebra/fspace.spad.pamphlet?r1=432&r2=585

Status: fixed somewhere => fix proposed




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