Use list() to get the coefficients: sage: P=x^3-2*x^2-x-2 sage: F125.<a>=GF(5^3,name='a',modulus=P) sage: b=a^37;b 4*a^2 + 3*a + 1 sage: Zy.<y> = ZZ[] sage: Zy(list(b)) 4*y^2 + 3*y + 1
On Wednesday, 27 November 2024 at 06:51:57 UTC Dima Pasechnik wrote: > A natural way would be to construct the quotient ring of GF(5)[x] modulo > (P), then b will be a polynomial in x, and you will have direct access to > its coefficients. > > > On 26 November 2024 16:46:50 GMT-06:00, "G. M.-S." <list...@gmail.com> > wrote: > >> >> Already asked on >> >> https://ask.sagemath.org/question/80389/conversion-from-finite-field-to-integer-polynomial >> >> I am looking for a function myf doing the following: >> >> sage: var('x') >> x >> sage: P=x^3-2*x^2-x-2 >> sage: F125.<a>=GF(5^3,name='a',modulus=P) >> sage: b=a^37;b >> 4*a^2 + 3*a + 1 >> sage: c=myf(b,y) >> 1 + 3*y + 4*y^2 >> sage: c.parent() >> Power Series Ring in y over Integer Ring >> >> or better still (symmetric representation): >> >> sage: c=myf(b,y) >> 1 - 2*y - y^2 >> sage: c.parent() >> Power Series Ring in y over Integer Ring >> >> I can manage with str, replace, preparse, eval but there is surely a >> natural way. >> >> TIA, >> >> Guillermo >> >> -- 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 view this discussion visit https://groups.google.com/d/msgid/sage-support/453487fb-6288-4335-a457-e6f58ed47e78n%40googlegroups.com.
