Fix the issue trekhleb#9.

Author: trekhleb

homemade/linear_regression/linear_regression.py

@@ -102,7 +102,7 @@ def gradient_step(self, alpha, lambda_param):
  # Vectorized version of gradient descent.
  theta = theta * reg_param - alpha * (1 / num_examples) * (delta.T @ self.data).T
  # We should NOT regularize the parameter theta_zero.
- theta[1] = theta[1] - alpha * (1 / num_examples) * (self.data[:, 0].T @ delta).T
+ theta[0] = theta[0] - alpha * (1 / num_examples) * (self.data[:, 0].T @ delta).T
 
  self.theta = theta