Try Maxima: taylor(1/(x+x^2),x,0,3) gives 1/x-1+x-x^2+x^3 ....
which may be what you want. But I'm not sure because the text you quote looks like gobbledygook. RJF On Monday, July 9, 2012 1:27:30 AM UTC-7, John Cremona wrote: > > A colleague reported this, which looks like a bug to me. This is in > Sage-5.1.rc0. Note that g.prec() is only 19 though f.prec() is > Infinity. > > John > > I'm not sure who to bother about this, so I thought I could ask you. > Here is a version of a Sage behaviour (feature? bug?) that bit me > recently. > > sage: R, x = PowerSeriesRing(ZZ, 'x', default_prec = 80).objgen() > sage: f = x + x^2 > sage: f.parent() > Power Series Ring in x over Integer Ring > sage: f.parent().default_prec() > 80 > sage: g = 1/f > sage: g.parent() > Laurent Series Ring in x over Integer Ring > sage: g.parent().default_prec() > 20 (??????) > sage: h = 1/2 * f > sage: h.parent() > Power Series Ring in x over Rational Field > sage: h.parent().default_prec() > 80 > > That was a big surprise to me! Sometimes the precision is carried > over to the new ring, and sometimes it isn't? Now that I've found > this, I can catch it my code, but it does seem strange... It seems > more reasonable for the precision to always be carried over? > > Am I confused here? > > best, > > saul > -- -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
