ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Mon, 06 Jul 2020 21:18:17 +0200exact computations with algebraic numbershttps://ask.sagemath.org/question/52362/exact-computations-with-algebraic-numbers/I'm trying to do exact computations with algebraic numbers. In particular, I know to expect integer answers like `1`, `0`, and `3` at the end of my computations, but I'm getting something slightly off.
I noticed that if I run
sage: r = sqrt(2)
sage: a = AA(r)
sage: b = AA(1/r)
sage: c = a*b
Then I get:
sage: c
1.000000000000000?
Is this being handled in the computer as exactly `1`? Otherwise, how can I do exact computations with algebraic numbers in Sage? I obtain the algebraic numbers I'm working with using `algdep()` to find a polynomial and `.roots(QQbar)` to find the roots of that polynomial.b897069Mon, 06 Jul 2020 21:18:17 +0200https://ask.sagemath.org/question/52362/