[Axiom-developer] possible bug

[Martin Rubey]

I'd be very grateful if somebody could look at the input file below. (Don't be
afraid, most of the definitions are not needed)

I would have thought that bug() would yield twice the same thing.  It may be a
mistake on my side, of course, but note that

* axiom does not compute 

  map(c +-> sqrtrule c, series(first Phi Psi Phi [x,y,Z.2], t=0)::ULS(EXPR INT, 
t, 0))

* neither axiom nor fricas can compute

  map(c +-> sqrtrule c, series(first Phi Psi Phi [x,y,Z.2], t=0)::ULS(EXPR INT, 
t, 0))-first Phi Psi Phi [x,y,Z2]


since this is actual work, I'd be extremely grateful for help!

Martin

-------------------------------------------------------------------------------
K := ((t*y+t*x)*z*z+(t*y*y+(-x*y)+t*x*x)*z+t*x*y*y+t*x*x*y)
Z := zerosOf(K, z)

sqrtrule := rule sqrt(a^2*?b) == a*sqrt b
Z1 := map(c +-> sqrtrule c, series(Z.1, t=0)::ULS(EXPR INT, t, 0))::ULS(FRAC 
POLY INT, t, 0)
Z2 := map(c +-> sqrtrule c, series(Z.2, t=0)::ULS(EXPR INT, t, 0))::ULS(FRAC 
POLY INT, t, 0)

Phi l == [l.2 * l.3/ l.1, l.2, l.3]

Psi l == [l.1, l.1 * l.3/l.2, l.3]

-- I guess the following is a bug:
-- I cannot even subtract the two!
bug() == 
    output map(c +-> sqrtrule c, series(first Phi Psi Phi [x,y,Z.2], 
t=0)::ULS(EXPR INT, t, 0))
    output first Phi Psi Phi [x,y,Z2]