isn't the standard that for positive numbers the principle root is always returned? (even though there is negative and positive ones)
On Monday, January 15, 2024 at 7:20:29 AM UTC-6 oldk1331 wrote: > Thanks for the explanation... > > Now the final puzzle over algebraic number for me is: > why sqrt(4) gives 2, instead of both roots? > > - Qian > > On 1/15/24 19:55, Waldek Hebisch wrote: > > On Mon, Jan 15, 2024 at 06:20:45PM +0800, Qian Yun wrote: > >> sqrt(1/x) no longer simplifies to 1/sqrt(x) after the > >> "Disable splitting of roots" commit. > > > > Well, this was blocked around 2006. Consider x = -1/2 (example > > from bug6357.input). After such transform principal branch > > rule gives different root. > > > > > >> But sqrt(1/x) and sqrt(x) are algebraically dependent kernels, right? > >> > >> So it should be a good idea to do the simplification, to lower the > >> chance of introducing algebraically dependent kernels. > > > > Such things (and more) should be handled in 'normalize'. Currently > > 'normalize' is quite weak when dealing with algebraic kernels, > > but this is going to change. > > > -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/fricas-devel/1e0711c3-3ce1-4122-bb5f-42225c2afdc6n%40googlegroups.com.
