Hi Sara Pashmin,
I assume you read the documentation for fourier_elim. fourier_elim is a
very powerfull tool, but I am afraid that I am not very familiar with it.
Perhaps some else can be of more help. But I will give it a try:
(%i1) load(fourier_elim);
(%o1) /usr/share/maxima/5.26.0/share/contrib/fourier_elim/fourier_elim.lisp
(%i2) load(solve_rat_ineq);
(%o2) /usr/share/maxima/5.26.0/share/contrib/solve_rat_ineq.mac
(%i3) sol : solve_rat_ineq(x^2-9 < 0);
(%o3) [[x > - 3, x < 3]]
(%i4) fourier_elim(append(sol[1], [x < 0]), [x]);
(%o4) [- 3 < x, x < 0]
solve_rat_ineq is not documented at the moment, but you will find some
examples inside of the file share/contrib/solve_rat_ineq.mac itself.
Maybe you can generally use solve_rat_ineq to return a list of linear
inequalities, append them and let fourier_elim do the rest. However
solve_rat_ineq ist restricted to rational expressions.
Hope that helps
Vollker van Nek
By the way. Some of your paranthesises aren't necessary.
2012/3/27 Sara Pashmin <sarapashm at googlemail.com>
> Thanks, Volker. It was helpful.
>
> Now my only problem is to solve of the inqualities: [((x)^2-8)<0 , (x)<0].
>
> For the inaualities: [((x)^2-9)<0 , (x)<0] :
> fourier_elim( [((x)^2-9)<0 , (x)<0], [x]);
> I get the satisfied answer:
> [-3<x,x<0]
>
> But the solve of the first inaualities is:
>
> [ x<0, -(x^2-8)>0]
>
> I tried to use the functions of equalities like "allroots (eqn)" and
> "bfallroots (eqn)" but they were not helpful.
>
> Regards
>
> Sara Pashmin
>
>
> Am 27. M?rz 2012 16:24 schrieb Volker van Nek <volkervannek at googlemail.com
> >:
> > (%i1) display(foo)$
> > foo = foo
> >
> > (%i2) disp(foo)$
> > foo
> >
> > Maybe disp is what you want.
> >
> > Volker van Nek
> >
> > 2012/3/27 Sara Pashmin <sarapashm at googlemail.com>
> >>
> >> Hello,
> >>
> >> I try to solve inequalities of a list with Maxima.
> >>
> >> A simple example is:
> >>
> >> load(to_poly_solver) $
> >> y : [1,4,8]$
> >> for i:1 step 1 thru length(y) do
> >> ( tt[i]: %solve( [(x[i]^2-y[i])<0, (x[i])<0], [x[i]]),
> >> display (tt[i])
> >> );
> >>
> >> the answer:
> >>
> >> (%o144) [1,4,8]
> >> tt[1]=%union([-1<x[1],x[1]<0])
> >> tt[2]=%union([-2<x[2],x[2]<0])
> >> tt[3]=%union([x[3]<0,-(x[3]^2-8)>0])
> >> (%o145)
> >>
> >> I would like to know :
> >>
> >> 1) how to get a result of tt[3] like that:
> >>
> >> %union( [x[3]<0 , x[3]>-2.828])
> >>
> >> and:
> >> 2) how to display the results of "x" without using "display (tt[i])".
> >> For example when I use the single variable (without list and "for") like
> >> this:
> >> y : 8$
> >> %solve( [(x^2-y)<0, (x)<0], [x]);
> >> I get the following result of x:
> >> (%o157) %union([x<0,-(x^2-8)>0])
> >>
> >> I will be thankfur for help,
> >>
> >> Best Regards
> >>
> >> Sarah
> >> _______________________________________________
> >> Maxima mailing list
> >> Maxima at math.utexas.edu
> >> http://www.math.utexas.edu/mailman/listinfo/maxima
> >
> >
>