Maybe you intended
(12) -> sx_test:=series(x,x=0)*s_test
(12)
2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 10 10 11
x + a x + a x + a x + a x + a x + a x + a x + a x + a x + a x
+
12
O(x )
Type: UnivariatePuiseuxSeries(Expression(Integer),x,0)
(13) -> coefficient(sx_test,4)
3
(13) a
Type: Expression(Integer)
On 14 April 2017 at 13:27, Raymond <[email protected]> wrote:
> In my ongoing interest in combinatorics there seems to be lapse in
> Axiom/Fricas
> In the attached script (repeated below) investigating "series(f,x=0)"
> I can correctly differentiate, integrate, add, and subtract correctly; but
> not multiply.
> One of the rules for the Method of Coefficients is
> [t^n](t*f(t))=[t^(n-1)] f(t)
> The internal multiplication by the indexing variable is used elsewhere as
> well.
> Is there any way to append the multiply operation into
> GeneralUnivariatePowerSeries or UnivariatePuiseuxSeries? Or do I have to
> define a new domain or some such? That does seem to be a waste.
> --
> I guess that I will have to make a list [f(t),[t^n]f(t)] i.e. [generating
> function, term n] in order to access the series for f(t) in the blind. That
> is ask about [t^n]f(t) when n is not instantiated. Even though the
> diff...add rules seem to have a grasp on the coefficients and _seems_ to
> understand the generating function f(t) (I could be wrong here).
> --
> Ray
>
> s_test:= series(1/(1-a*x) ,x=0)
> ++ Now I can differentiate
> D(s_test,x)
> ++ Integrate
> integrate(s_test,x)
> ++ Add
> s1_test:=series(1/(1-b*x),x=0)
> ss_test:=s_test+s1_test
> coefficient(ss_test,4)
> ++
> ++ But I can't multiply
> sx_test:=x*s_test
> coefficient(sx_test,4)
> D(sx_test,x)
> ++ Random Leibniz product rule test
> ++ D(x*s_test,x)-x*D(s_test,x)-s_test
> ++
> ++ And just a puzzle to me
> ++ (x^2 * x^4)
> ++ x^r * x^s
>
>
>
> --
> You received this message because you are subscribed to the Google Groups
> "FriCAS - computer algebra system" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to [email protected].
> To post to this group, send email to [email protected].
> Visit this group at https://groups.google.com/group/fricas-devel.
> For more options, visit https://groups.google.com/d/optout.
--
You received this message because you are subscribed to the Google Groups
"FriCAS - computer algebra system" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
Visit this group at https://groups.google.com/group/fricas-devel.
For more options, visit https://groups.google.com/d/optout.
