MuPad vs Maxima



-----maxima-bounces at math.utexas.edu wrote: -----


>One?thing?I?do?find?disappointing?is?that?there?doesn't?seem?to?be?a
>straightforward?way?to?solve?inequalities?in?maxima?(if?I'm?mistaken,
>please?do?correct?me).

To solve inequalities, use either to_poly_solver (calls Fourier elimination)
or solve_rat_ineq. The to_poly_solver solves linear inequalities and some 
(not many) nonlinear inequalities:

(%i1) load(to_poly_solver)$
Loading maxima-grobner $Revision: 1.6 $ $Date: 2009/06/02 07:49:49 $

(%i6) %solve(x > max(3,10-x/5),x);
(%o6) %union([25/3<x])

(%i12) %solve(abs(1-abs(2-abs(x))) < 5,x);
(%o12) %union([-8<x,x<-2],[-2<x,x<0],[0<x,x<2],[2<x,x<8],[x=-2],[x=0],[x=2])

(%i24) %solve([5*x + y < 10, x - y > 12, x + 7*y < 12],[y,x]);
(%o24) %union([y+12<x,x<2-y/5,y<-25/3])

There is also solve_rat_ineq; this package might be better with nonlinear
inequalities in one variable:

(%i25) load(solve_rat_ineq)$
(%i26) solve_rat_ineq((x-1)^2*(x+1)>0);
(%o26) [[x>-1,x<1],[x>1]]

Also, the Wester tests are in a folder ../tests/wester_problems, but the tests
aren't in a form that Maxima can automatically run (with run_testsuite). Maybe 
you would like to convert the Wester tests into the Maxima regression test form
of input followed by expected output:

 diff(x^2,x);
 2*x$

 diff(x^4,x);
 4*x^3$


--Barton