Re: [sage-support] power series algebraic over field of rational fractions

2015-04-02 Thread John Cremona
Sorry, I misunderstood your question which is harder (and more interesting!) than I thought. I hope there will be some creative suggestions. John On 2 April 2015 at 17:22, Pierre wrote: > PS sorry i wrote > >> to be clear : i know there is at least a relation >> >> P_0(x) + P_1(x) f + P_2(x) f^

Re: [sage-support] power series algebraic over field of rational fractions

2015-04-02 Thread Pierre
PS sorry i wrote to be clear : i know there is at least a relation > > P_0(x) + P_1(x) f + P_2(x) f^2 + ... + P_d(x) f^d > i meant to end with " = 0 ". -- You received this message because you are subscribed to the Google Groups "sage-support" group. To unsubscribe from this group and stop r

Re: [sage-support] power series algebraic over field of rational fractions

2015-04-02 Thread Pierre
> Given a degree bound d in y, you are looking for a linear relation > between 1, f, f^2, ..., f^d, which you could find using linear > algebra over K after making sure that you have at least d+1 > I'm looking for a linear relation with coefficients in K(x), so you probably mean linear alge

Re: [sage-support] power series algebraic over field of rational fractions

2015-04-02 Thread John Cremona
On 2 April 2015 at 16:13, Pierre wrote: > Hi, > > I have a power series f in K[[x]] where K is a finite field, and I know that > it is algebraic over K(x). I'm looking for an explicit polynomial P in K[x, > y] such that P(x, f) = 0. I can figure out a bound for the degree of P in y, > in my exampl

[sage-support] power series algebraic over field of rational fractions

2015-04-02 Thread Pierre
Hi, I have a power series f in K[[x]] where K is a finite field, and I know that it is algebraic over K(x). I'm looking for an explicit polynomial P in K[x, y] such that P(x, f) = 0. I can figure out a bound for the degree of P in y, in my example (though not in x). Given this post https://g