--- C Y wrote:
> 2 2 4 6
> kg kg m kg m
> (c) (--) + ((- a e) (------)) ("*"()) + ((b d) (------)) ("*"())
> s 4 8
> s s
Well, "*"() is what gets printed for a multiplication
operator without any arguments, i.e., it is what is shown by
:lisp (displa '((mtimes))) .
So my guess is that the function you wrote is moving
terms out of one multiplication operator and into another,
and sometimes that leaves the first one with no arguments.
Maybe you want to test to see if rearrangement removes
all the operands, and if so just substitute 1 or something.
Or maybe it just needs an extra round of simplification --
:lisp (simplifya '((mtimes)) nil) yields 1. I think an
explicit call to ev would have that effect (among others).
Just thinking out loud here.
Hope this helps,
Robert Dodier
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