Le mardi 2 juillet 2013 02:38:44 UTC+2, rjf a écrit : > > > > What you've written is just a hack. > Of course it's a hack; this is why I did not submit it as a patch for Sage. As far as one restricts oneself to the REAL DOMAIN, I think it works. Please show me a counter-example.
Again, let me insist: it is elementary mathematics that sqrt: R+ --> R+, x |--> sqrt(x) is a ONE-TO-ONE map, the reverse of which is R+ --> R+, x |--> x^2 I think everybody agrees that when working only with real variables, this is the standard meaning of the sqrt function. Then it must obey sqrt(x^2) = abs(x) and the above hack simply ensures this. This is why I called it 'simplify_sqrt_real' to insist that it is valid only for REAL-valued expressions of REAL variables. -- 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/groups/opt_out.
