Hello, > 1. The solve wrapper of maxima does some nice stuff symbolically, but > of course it can't handle everything, like > > sage: solve(x^5-x-12,x) > [0 == x^5 - x - 12] > > which makes sense! But I poked around a little for a numerical > approximation of solutions command and didn't find it. This probably > means I just didn't look in the right places - any ideas? I > understand Mathematica calls this sort of thing nsolve, but I really > don't know.
Your best is to use Sage's actual polynomial objects instead of symbolic expressions (if you're just interested in polynomial expressions). sage: R.<y> = ZZ[] sage: a = y^5 - y - 12 sage: a.roots(RR) [(1.68758384186451, 1)] sage: a.roots(CC) [(1.68758384186451, 1), (0.472524075221555 + 1.59046294160722*I, 1), (0.472524075221555 - 1.59046294160722*I, 1), (-1.31631599615381 + 0.922151856490895*I, 1), (-1.31631599615381 - 0.922151856490895*I, 1)] If you want to use symbolic expressions, you can use the .find_root() method. sage: a = x^5 - x - 12 sage: a.find_root(0,2) 1.6875838418645157 > 2. How far does Sage recognize complex numbers a priori? For > instance, > > sage: abs(1+i) > sqrt(2) > > but pretty much anything else doesn't seem to recognize it, as indeed Sage on startup predefines i in the same way it predefines x. (This is in sage.all_cmdline and sage.all_notebook.) Here's what's going on: sage: j = I() sage: abs(1+j) sqrt(2) > A followup would be to ask if any of those functions have functional > notation; there are lots of functions for CC, but they mostly seem to > use object notation. What methods did you have in mind? > > 3. I remember that at some point implicit coefficient multiplication > was implemented, e.g. Implicit multiplication is turned off by default. You can turn it on: sage: implicit_multiplication(True) sage: 2x 2*x --Mike --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
