Relying on what Maxima does for infinities is probably not a great tactic. There are two models, conflicting and yet both in use. And neither one quite covers what you might want. See http://people.eecs.berkeley.edu/~fateman/papers/infinity.pdf
for some discussion. Is there "one point" where +-infinity sits? or would that place be "undefined"? or you might want something like Mathematica's DirectedInfinity. Comments on that (draft) paper above are welcome. RJF On Tuesday, June 7, 2016 at 1:53:33 PM UTC-7, john_perry_usm wrote: > > I should elaborate on this after rereading the limit documentation more > carefully. It states: > > Return the limit as the variable v approaches a from the given > direction. > > expr.limit(x = a) > expr.limit(x = a, dir='above') > > INPUT: > > * "dir" - (default: None); dir may have the value 'plus' (or '+' > or 'right') for a limit from above, 'minus' (or '-' or 'left') > for a limit from below, or may be omitted (implying a two-sided > limit is to be computed). > > The second expression (right before INPUT) seems to imply that the default > value for dir is 'above'. That might explain why Sage hands back Infinity, > but the description of "dir" implies that the default is None. > > So I'm totally confused. > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
