maxima-bounces at math.utexas.edu wrote on 09/08/2009 11:21:55 AM:
>
> This is caused by the following in simplimit:
>
> (defmfun simplimit (exp var val &aux op)
> (cond
> ((eq var exp) val)
> ((or (atom exp) (mnump exp)) exp)
> ((and (not (infinityp val))
> ;; *** HERE ***
> (not (amongl '(%sin %cos %atanh %cosh %sinh %tanh mfactorial %log)
> exp))
> (not (inf-typep exp))
> (simplimsubst val exp)))
>
> Since hypergeometric isn't among the list of "special" functions,
> simplimsubst is called.
Thanks--Maxima should have a function that *tries* to determine if an
expression is continuous on an interval--this function should be somewhat
better than the average freshman calculus student, and it should use
object-oriented function dispatch so that it can be extended without
appending more cases to a conditional. Such a function would be useful for
integrate and limit.
Barton
P.S. By the way, I noticed:
(%i1) limit(sin(%pi * x),x,inf);
(%o1) ind
(%i2) declare(x,integer)$
(%i3) limit(sin(%pi * x),x,inf);
(%o3) 0
See TE 1 on page 5 of
http://www.unk.edu/uploadedFiles/facstaff/profiles/willisb/six-facts-mostly-about-sums.pdf