def test_derivative(self):
with self.subTest('Derivative of constant is 0'):
t = Term.constant(2)
expected = Term.constant(0)
self.assertEqual(expected, t.derivative())
with self.subTest('Derivative of 2*x^1'):
t = Term(coeff=2, variable='x', power=1)
expected = Term.constant(2)
self.assertEqual(expected, t.derivative())
with self.subTest('Derivative of x^1'):
t = Term(coeff=1, variable='x', power=1)
expected = Term.constant(1)
self.assertEqual(expected, t.derivative())
with self.subTest('Derivative of 2*x^2'):
t = Term(coeff=2, variable='x', power=2)
expected = Term(coeff=4, variable='x', power=1)
self.assertEqual(expected, t.derivative())
def test_term_derivative_is_calculated_as_expected_with_coeffiecient_variable_and_power(
self):
test_list = [2, True, 5]
test_obj = Term(test_list)
self.assertEqual(test_obj.derivative(), '10x^4')
def test_term_derivative_is_calculated_expected_with_only_coefficient_and_variable(
self):
test_list = [3, True, None]
test_obj = Term(test_list)
self.assertEqual(test_obj.derivative(), '3')
def test_term_derivative_is_calculated_as_expected_with_only_variable_and_power(
self):
test_list = [None, True, 3]
test_obj = Term(test_list)
self.assertEqual(test_obj.derivative(), '3x^2')
def test_term_derivative_is_calculated_as_expected_with_only_coefficient(
self):
test_list = [1, False, None]
test_obj = Term(test_list)
self.assertEqual(test_obj.derivative(), '0')