On Mon, Apr 21, 2008 at 9:22 AM, Aleksandr <[EMAIL PROTECTED]> wrote: > > In what version of Sage was n implemented for matrices? Right now, > N(m) gives an error in my version 2.9.2
This is *only* in Sage-3.0, which hasn't been released yet. There you will be able to do: sage: m = matrix([[2,3], [pi, e]]) sage: N(m) [2.00000000000000 3.00000000000000] [3.14159265358979 2.71828182845905] Don't worry, Sage-3.0 is not vaporware. -- William > > sage: N(m) > --------------------------------------------------------------------------- > <type 'exceptions.TypeError'> Traceback (most recent call > last) > > /home/sasha/<ipython console> in <module>() > > /opt/sage/local/lib/python2.5/site-packages/sage/misc/functional.py in > numerical_approx(x, prec, digits) > 732 return sage.rings.real_mpfr.RealField(prec)(x) > 733 except TypeError: > --> 734 return sage.rings.complex_field.ComplexField(prec) > (x) > 735 > 736 n = numerical_approx > > /opt/sage/local/lib/python2.5/site-packages/sage/rings/ > complex_field.py in __call__(self, x, im) > 207 except AttributeError: > 208 pass > --> 209 return complex_number.ComplexNumber(self, x, im) > 210 > 211 def _coerce_impl(self, x): > > /home/sasha/complex_number.pyx in > sage.rings.complex_number.ComplexNumber.__init__() > > <type 'exceptions.TypeError'>: unable to coerce to a ComplexNumber > > > > On Apr 21, 6:51 am, Jason Grout <[EMAIL PROTECTED]> wrote: > > Simon King wrote: > > >> ... and since you wanted amatrixof *numbers* out of m, you may do > > > >> sage: m(1.,2.) > > > > > Oops, i just see that your original example was x=pi/2, y=pi. That is > > > fine: > > > sage: m(pi/2,pi) > > > [0 0] > > > [0 0] > > > > > and is of course better than going via RR: > > > sage: m(RR(pi/2),RR(pi)) > > > [ 6.12323399573676e-17 0] > > > [ 0 -1.224646799147353e-16] > > > > I don't have the source/sage system handy, but I think the n() function > > was implemented recently for symbolic matrices, so the following should > > work and be consistent with other things in Sage (example off the top of > > my head with hand-constructed output, but something like this should be > > possible soon, if not now): > > > > sage: m(1,2).n() > > [ 0.540302305868140 0] > > [ 0 -0.909297426825682] > > > > Seehttp://trac.sagemath.org/sage_trac/ticket/2857 > > > > > > -Jason > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] 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 -~----------~----~----~----~------~----~------~--~---
