On 6/30/08, Barton Willis <willisb at unk.edu> wrote:
> (%i1) load(fourier_elim)$
> (%i2) fourier_elim([x[2]+x[1]<1,x[1]-x[2]>-1],[x[1],x[2]]);
>
> Maxima encountered a Lisp error:
>
> Error during processing of --eval option "(cl-user::run)":
>
> The value NIL is not of type CHARACTER.
I find GCL + CVS Maxima does not trigger the error. But tracing
OUTPUT-TEXT* shows that NIL is indeed in the arguments sometimes.
SBCL or CMUCL + CVS Maxima => error message about NIL;
I guess they are checking the arguments more carefully.
Incidentally OUTPUT-TEXT* is called as part of the construction of a
gensym with a name like "x[1]2939". Sometimes one of the characters
of "x[1]" is null (always the left paren, in the instances I have found).
Dunno how that happened; I think the list of characters is whatever
is returned by EXPLODEN or something like that.
HTH
Robert Dodier