I would have never guessed that list(b) works. Should there be b.list() or b.coefs() ?
On 27 November 2024 02:48:05 GMT-06:00, John Cremona <john.crem...@gmail.com> wrote: >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. -- 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/54124DFC-F30D-4779-9793-8C45C937D21A%40gmail.com.
