def test_diff_series():
# issue sympy/sympy#11313
# test Derivative series & as_leading_term
assert Derivative(x**3 + x**4, x).as_leading_term(x).doit() == 3 * x**2
s = Derivative(sin(x), x).series(x, n=3)
assert s == Derivative(-x**3 / 6, x) + Derivative(x, x) + O(x**3)
assert s.doit() == 1 - x**2 / 2 + O(x**3)
def test_doit():
n = Symbol('n', integer=True)
f = Sum(2 * n * x, (n, 1, 3))
d = Derivative(f, x)
assert d.doit() == 12
assert d.doit(deep=False) == Sum(2 * n, (n, 1, 3))
def test_sympyissue_11313():
# test Derivative series & as_leading_term
assert Derivative(x**3 + x**4, x).as_leading_term(x).doit() == 3*x**2
s = Derivative(sin(x), x).series(x, n=3)
assert s == Derivative(-x**3/6, x) + Derivative(x, x) + O(x**3)
assert s.doit() == 1 - x**2/2 + O(x**3)
def test_doit():
n = Symbol('n', integer=True)
f = Sum(2 * n * x, (n, 1, 3))
d = Derivative(f, x)
assert d.doit() == 12
assert d.doit(deep=False) == Sum(2*n, (n, 1, 3))