Thanks! On Tuesday, September 27, 2022 at 3:02:25 PM UTC+1 Kwankyu wrote:
> This bug is tracked now in > > https://trac.sagemath.org/ticket/34591 > > On Tuesday, September 27, 2022 at 6:31:39 PM UTC+9 wdjo...@gmail.com > wrote: > >> On Tue, Sep 27, 2022 at 4:46 AM John Cremona <john.c...@gmail.com> wrote: >> > >> > Am I doing something stupid here, or is this a bug? >> > >> > sage: R = Integers(8) >> > sage: RXY.<X,Y> = R[] >> > sage: F = X^3-X^2*Y+X*Y^2+Y^3 >> > sage: F([4,2]) >> > 6 >> > sage: 4^3-4^2*2+4*2^2+2^3 >> > 56 >> > sage: (4^3-4^2*2+4*2^2+2^3) % 8 >> > 0 >> > >> >> Even after coercion it doesn't evaluate in ZZ/8ZZ: >> >> sage: ZZ8 = IntegerModRing(8) >> sage: R.<x,y> = PolynomialRing(ZZ8, "x,y") >> sage: f = x^3-x^2*y+x*y^2+y^3 >> sage: x0 = ZZ8(4) >> sage: y0 = ZZ8(2) >> sage: x0^3-x0^2*y0+x0*y0^2+y0^3 >> 0 >> sage: f(x0,y0) >> 6 >> sage: f(4,2) >> 6 >> >> > >> > Why does F not evaluate to 0 mod 8 at X=4, Y=2? Rather obviously, each >> > of the terms in F(4,2) is 0 mod 8. >> > >> > John >> > >> > -- >> > 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...@googlegroups.com. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/sage-support/CAD0p0K5hXexw5J20gstKUOXxzWdP2a2OTRbKmUtAyG41ySSR-A%40mail.gmail.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 on the web visit https://groups.google.com/d/msgid/sage-support/a3bf46f4-f359-476d-897f-302ac3838cean%40googlegroups.com.
