problem with 'is zero or nonzero'

>>>>> "Przemek" == Przemek Klosowski <przemek.klosowski at nist.gov> writes:

    Przemek> (Maxima 5.30.0 using Lisp SBCL 1.1.8-2 on Fedora 19)
    Przemek> I guess it is a Maxima-wide problem with resolving constant conditions, that I ran into back in
    Przemek> July for integrate()
    Przemek> and now with desolve().? Whenever Maxima asks 'Is ... zero or nonzero?' both? 'nonzero' and 'zero'
    Przemek> are interpreted as 'zero'.
    Przemek> I suspect the only way to specify non-zero is to say 'n':
    Przemek> atvalue ('diff (f(x), x), x = 0, v0)$
    Przemek> atvalue (f(x), x = 0, x0)$
    Przemek> desolve('diff(f(x),x,2)=-(w*w)*f(x), f(x));
    Przemek> Is w zero or nonzero?
    Przemek> nonzero;
    Przemek> (%o16)???????????????????????? f(x) = x0 + v0 x
    Przemek> desolve('diff(f(x),x,2)=-(w*w)*f(x), f(x));
    Przemek> Is w zero or nonzero?
    Przemek> n;
    Przemek> ?????????????????????????????????????????? ? ? ? ??? v0???????????????
    Przemek> (%o17)????????? f(x) = x0 cos(w x) + -----? sin(w x)
    Przemek> ???????????????????????????????????????????????????? w

This doesn't make sense. In your example, you answered nonzero
(nonzero, n) both times but got different answers. I don't get
that. Can you resend your test case again?  And use display2d:false,
too, to make it easier to read in email.

Ray