def probability_density(self, X):
        """Compute probability density.

        Arguments:
            X: `np.ndarray` of shape (n, 1).

        Returns:
            np.ndarray
        """
        self.check_fit()
        return norm.pdf(X, loc=self.mean, scale=self.std)
Compute probability density.

        Arguments:
            X: `np.ndarray` of shape (n, 1).

        Returns:
            np.ndarray