docs: def _get_gradient_log_pdf(self):
          """
          Method that finds gradient and its log at position
          """
          sub_vec = self.variable_assignments - self.model.mean.flatten()
          grad = - np.dot(self.model.precision_matrix, sub_vec)
          log_pdf = 0.5 * np.dot(sub_vec, grad)
  
          return grad, log_pdf