Hi Georg, On 2015-06-02, ggrafendorfer <georg.grafendor...@gmail.com> wrote: > sage: g(x) = x^2 - 26*x -9 > sage: g.factor() > x^2 - 26*x - 9
First of all, what you create is a symbolic function, so, factorisation doesn't really make sense. sage: g(x) = x^2-26*x-9 sage: g x |--> x^2 - 26*x - 9 What you probably want to factor is a symbolic expression that isn't a function. Let's see if it works: sage: g = x^2-26*x-9 sage: g x^2 - 26*x - 9 sage: g.factor() x^2 - 26*x - 9 This time, the reason is that your expression lives in the symbolic ring, which is so large that the notion of factorisation doesn't really make sense (you could factor g as, say sin(x)*(g/sin(x))). sage: g.parent() Symbolic Ring So, instead of working with general symbolic expressions, you should work with actual polynomials, living in a polynomial ring with prescribed coefficient domain. Of course, the factorisation of your polynomial will depend on the coefficient domain: sage: R.<x> = ZZ[] sage: R Univariate Polynomial Ring in x over Integer Ring sage: g = x^2-26*x-9 sage: g.factor() x^2 - 26*x - 9 but when you work over the algebraic completion of QQ or if you work in RR or some other large enough coefficient domain, then g factors: sage: R.<x> = QQbar[] sage: g = x^2-26*x-9 sage: g.factor() (x - 26.34166406412634?) * (x + 0.3416640641263338?) sage: R.<x> = RR[] sage: g = x^2-26*x-9 sage: g.factor() (x - 26.3416640641263) * (x + 0.341664064126334) Best regards, Simon -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-support+unsubscr...@googlegroups.com. To post to this group, send email to sage-support@googlegroups.com. Visit this group at http://groups.google.com/group/sage-support. For more options, visit https://groups.google.com/d/optout.
