Le Thu, 09 Apr 2015 18:38:24 +0200, Vincent Delecroix <20100.delecr...@gmail.com> a écrit :
> Hello, > > I found > > sage: abs(sqrt(x)) > sqrt(abs(x)) > > much better than > > (%i1) abs(sqrt(x)); > (%o1) sqrt(x) > > We discussed in #15605 that variables in the symbolic ring should be > thougt as complex variables (if not specified otherwise). The maxima > version is wrong when x is real negative. > > What is the answer to > > sage: sqrt(abs(x)**2) == abs(x) > sage: abs(x**2) > sage: (-1)^(2/3) # see ticket 15605 I can't help but notice that under the convention that sqrt is a function from non-negative reals to non-negative reals, what maxima does makes perfect sense. Snark on #sagemath -- 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 http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
