another two bugs in solver



1. first bug

GCL (GNU Common Lisp)  Version(2.5.0) Sun Nov 17 15:58:09 CET 2002
Licensed under GNU Library General Public License
Contains Enhancements by W. Schelter
Maxima 5.9.0rc3 http://maxima.sourceforge.net
Distributed under the GNU Public License. See the file COPYING.
Dedicated to the memory of William Schelter.
This is a development version of Maxima. The function bug_report()
provides bug reporting information.
(C1) EquationP(e):=if part(e,0)="=" then true else false$

(C2) load("/usr/labri/rubey/maxima/src/binary-gcl/comm.o")$

(C3) load("/usr/labri/rubey/maxima/src/binary-gcl/mutils.o")$

(C4) load("/usr/labri/rubey/maxima/src/binary-gcl/set.o")$

(C5) load("algebra/solver/misc")$

(C6) load("algebra/solver/solver")$

(C7) display2d:false$

(C8) trace(solve)$

(C9) solver([u-t*(u^(l+1)+u+1) = 0,1-t*((l+1)*u^l+1) = 0],[u,t],[l]);

1 Enter SOLVE [(-l-1)*t*u^l-t+1,u]
Is  l  an integer?

y;
1 Exit  SOLVE [u = (1/(l*t+t)-t/(l*t+t))^(1/l)]
1 Enter SOLVE 
[-((l*((-(t-1)/((l+1)*t))^(1/l)+1)+1)*t-l*(-(t-1)/((l+1)*t))^(1/l))/(l+1),t]
1 Exit  SOLVE [t = 
l*(-(t-1)/((l+1)*t))^(1/l)/(l*(-(t-1)/((l+1)*t))^(1/l)+l+1)]
(D9) [[u = (-(t-1)/((l+1)*t))^(1/l),
       [-((l*((-(t-1)/((l+1)*t))^(1/l)+1)+1)*t-l*(-(t-1)/((l+1)*t))^(1/l))
	 /(l+1)]]]

The second item of the solution does not make t explicit, although solve 
did...

2. second bug (I think this is known, but I'm not sure)

the second time solver is invoked, it is silently assumed that l is an 
integer. I think this assumption should be removed...

I'll post all three as a bug report

Martin

Unfortunately, maxima starts to become unusable for me now. I'm unhappy.