class LinearRegressionTest(unittest.TestCase):
def setUp(self):
self.linreg = LinearRegression()
def test_dot_product_of_two_vectors_should_get_dot_product_result(self):
a = [1, 2, 3]
b = [4, 5, 6]
result = self.linreg.dot_product(a, b)
expected = 32
self.assertEquals(result, expected)
def test_dot_product_should_get_negative_if_vectors_have_different_length(
self
):
a = [1, 2, 3]
b = [4, 5, 6, 7]
result = self.linreg.dot_product(a, b)
expected = -1
self.assertEquals(result, expected)
def test_compute_cost_for_single_example_should_return_cost(self):
X = [[1, 2]]
y = [2]
theta = [0.1, 0.2]
result = self.linreg.compute_cost(X, y, theta)
expected = 1.125
self.assertEquals(result, expected)
def test_compute_cost_for_entire_examples_should_return_cost(self):
X = [[1, 2], [3, 4]]
y = [2, 2.5]
theta = [0.1, 0.2]
result = self.linreg.compute_cost(X, y, theta)
expected = 2.105
self.assertEquals(result, expected)
def test_run_gradient_descent_with_one_iteration_should_change_theta(self):
X = [[1, 2], [3, 4]]
y = [2, 2.5]
theta = [0, 0]
number_of_iterations = 1
result = self.linreg.run_gradient_descent(X, y, theta, number_of_iterations)
expected = (
[2.6572999999999993],
[0.07, 0.16]
)
self.assertEquals(result, expected)
def test_run_gradient_descent_with_ten_iteration_should_change_theta(self):
X = [[1, 2], [3, 4]]
y = [2, 2.5]
theta = [0, 0]
number_of_iterations = 10
result = self.linreg.run_gradient_descent(X, y, theta, number_of_iterations)
expected = (
[
2.6572999999999993,
1.4340467700000001,
0.8330420285729998,
0.5415905512402678,
0.4029957986666608,
0.339058852804416,
0.31098737943231103,
0.2997051253564717,
0.2959527141041505,
0.2953245352067722
],
[0.21850056185143937, 0.5469413946894416]
)
self.assertEquals(result, expected)
