- sage: set_random_seed()
- sage: J = ComplexHermitianEJA(3)
- sage: x = J.random_element()
- sage: while not x.is_invertible():
- ....: x = J.random_element()
- sage: r = J.rank()
- sage: a = x.characteristic_polynomial().coefficients(sparse=False)
- sage: expected = (-1)^(r+1)/x.det()
- sage: expected *= sum( a[i+1]*x^i for i in range(r) )
- sage: x.inverse() == expected
+ sage: set_random_seed() # long time
+ sage: J = random_eja(field=QQ, orthonormalize=False) # long time
+ sage: x = J.random_element() # long time
+ sage: while not x.is_invertible(): # long time
+ ....: x = J.random_element() # long time
+ sage: slow = x.inverse() # long time
+ sage: _ = J._charpoly_coefficients() # long time
+ sage: fast = x.inverse() # long time
+ sage: slow == fast # long time