def build_columns ( self , X , verbose = False ) : return sp . sparse . csc_matrix ( X [ : , self . feature ] [ : , np . newaxis ] )
python sparse matrix features name
construct the model matrix columns for the term
def build_columns(self, X, verbose=False):
        """construct the model matrix columns for the term

        Parameters
        ----------
        X : array-like
            Input dataset with n rows

        verbose : bool
            whether to show warnings

        Returns
        -------
        scipy sparse array with n rows
        """
        return sp.sparse.csc_matrix(X[:, self.feature][:, np.newaxis])