Conversion of number field elements to algebraic numbers #13041
Description
Implement a basic (but better than nothing) conversion of elements of number fields embedded into the complex numbers to elements of QQbar.
Origininal report:
sage: C.<z> = CyclotomicField(7)
sage: a = 2*z^2 + 5*z^4
sage: E = C.algebraic_closure()
sage: E(a)
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TypeError Traceback (most recent call last)
<snip>
TypeError: Illegal initializer for algebraic number
Component: algebra
Keywords: sd40.5
Author: Marc Mezzarobba
Branch/Commit: b28381a
Reviewer: Vincent Delecroix
Issue created by migration from https://trac.sagemath.org/ticket/13041