> > Thanks for the link! This is quite instructive. > > Indeed. Perhaps we should point this out in our documentation for `abs`.
> Le mardi 16 septembre 2014 11:41:42 UTC+2, Peter Bruin a écrit : >> >> PS: the following message from the Maxima mailing list (found via a >> different sqrt-related report in the Maxima bug tracker) is quite >> useful: >> >> https://www.ma.utexas.edu/pipermail/maxima/2011/025213.html >> >> From that page: >> >> * abs is a mathematical function which has simplification rules. It >> assumes by default that it is operating over the reals, so that for >> example >> abs(sqrt(x)) => sqrt(x) -- because sqrt is treated as a real-to-real >> function with domain and range 0..inf. But if there is an explicitly >> complex quantity (%i or a variable declared complex), that assumption is >> invalidated, so abs(z^2) => abs(z)^2, where declare(z,complex). >> >> -- 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.
