William Stein <wst...@gmail.com> writes: >> FriCAS give 0 for the input above, *but* this is only half of the story. >> In FriCAS (and Axiom, and I believe Sage too), the answer of a >> computation depends on the domain of the input. Eg.: >> >> (1) -> 0::INT^0::NNI >> >> (1) 1 >> Type: PositiveInteger >> (2) -> 0.0^0.0 >> >> >> Error detected within library code: >> 0^0 is undefined > > I'm confused. What does "0^0" precisely have to do with Johann's > question? I thought that since "binomial(x,1) = x" it would be > reasonable to defined binomial(-7,1) = -7. > > Are you writing at length about 0^0 only by analogy to give an example > of a function F(x) such that the value of F depends on the parent (or > type) of x such that applying F does not commute with some natural > inclusion of sets?
Exactly. Sorry for being lengthier than necessary, I guess I was pointing out something banal. > Or does 0^0 have something in particular to do with binomials? No, apart from a coincidental comment in Concrete Mathematics by Graham, Knuth, Patashnik (according to http://mathforum.org/dr.math/faq/faq.0.to.0.power.html on p.162). Martin --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
