Return this basis applied to X.

        Parameters
        ----------
        X: ndarray
            of shape (N, d) of observations where N is the number of samples,
            and d is the dimensionality of X.

        Returns
        -------
        ndarray:
            of shape (N, 1) of ones * self.offset.

def transform(self, X):
        """
        Return this basis applied to X.

        Parameters
        ----------
        X: ndarray
            of shape (N, d) of observations where N is the number of samples,
            and d is the dimensionality of X.

        Returns
        -------
        ndarray:
            of shape (N, 1) of ones * self.offset.
        """
        N = len(X)
        return np.ones((N, 1)) * self.offset