def decat_coef_inter_vec(cat):
    """
    De-concatenates a vector of the coefficient and intercept.

    Parameters
    ----------
    cat: array-like, shape (n_features + 1, )
        The concatenation of a coefficeint vector and intercept where
        the intercept is the first coordinate.

    Output
    -----
    coef, intercept

    coef: array-like, shape (n_features, )
        The coefficient vector.

    intercept: float
        The intercept.
    """
    return cat[1:], cat[0]