Minpoly and charpoly don't check their arguments correctly #13187
Description
The following fails in sage (likewise with charpoly):
k=CyclotomicField(10)
U=matrix(k, 1,1,[1])
var('t')
U.minpoly(t)
The error is in a call that the function makes to PolynomialRing :
TypeError: invalid input (Cyclotomic Field of order 10 and degree 4, t, None) to PolynomialRing function; please see the docstring for that function
Strangely, if you use :
k=CyclotomicField(10)
U=matrix(k, 1,1,[1])
var('t')
U.minpoly('t')
everything is fine.
In any case, I would expect charpoly/minpoly to complain themselves if I don't call them correctly (which isn't clear at all!) -- it's definitely not normal (and upsetting for newbies) that another function reacts.
This is with sage-5.1.beta6.
Component: linear algebra
Author: André Apitzsch
Reviewer: Robert Bradshaw
Merged: sage-5.2.beta1
Issue created by migration from https://trac.sagemath.org/ticket/13187