def test_is_extended_real():
x = Symbol('x', extended_real=True)
y = Symbol('y', extended_real=False)
z = Symbol('z')
assert is_extended_real(x)
assert not is_extended_real(y)
assert is_extended_real(z) is None
assert is_extended_real(z, Q.extended_real(z))
def split_real_imag(expr):
real_imag = lambda t: (
'real' if is_extended_real(t, assumptions) else 'imag'
if is_extended_real(I * t, assumptions) else None)
return sift(Add.make_args(expr), real_imag)