On 6/5/10 1:32 PM, Robert Dodier wrote:
> On 6/4/10, Barton Willis <willisb at unk.edu> wrote:
>
>
>> This is a bug; here is a related example:
>>
>> (%i1) dpart(sin(a+b),1);
>> Maxima encountered a Lisp error:
>>
> Seems to be a bug of recent origin; works OK in Maxima 5.20.0,
> not in 5.21.0.
>
> The problem might or might not be in dpart, I can't tell;
> I can't get a useful stack trace out of GCL (no relevant info),
> Clisp (crash), or Clozure CL (crash).
>
FWIW, I tested this with cmucl and pressed C-c to stop it. The back
trace appears to indicate that the problem is in simp-%sin which calls
apply-reflection-simp which calls odd-reflection-select which calls
simp-%sin. The argument to simp-%sin appears to alternate between
(SIMP-%SIN ((%SIN) ((MTIMES SIMP) -1 ((MBOX SIMP) (# $A $B))))
((MTIMES SIMP) -1 ((MBOX SIMP) ((MPLUS SIMP) $A $B)))
MTIMES)
and
(SIMP-%SIN ((%SIN) ((MBOX SIMP) ((MPLUS SIMP) $A $B)))
((MBOX SIMP) ((MPLUS SIMP) $A $B))
MBOX)
I guess the mbox is confusing odd-reflection-select.
I haven't investigated more yet....
Ray