Returns an interpolated point cloud following the dissimilarity matrix C
    using SMACOF multidimensional scaling (MDS) in specific dimensionned
    target space

    Parameters
    ----------
    C : ndarray, shape (ns, ns)
        dissimilarity matrix
    dim : int
          dimension of the targeted space
    max_iter :  int
        Maximum number of iterations of the SMACOF algorithm for a single run
    eps : float
        relative tolerance w.r.t stress to declare converge

    Returns
    -------
    npos : ndarray, shape (R, dim)
           Embedded coordinates of the interpolated point cloud (defined with
           one isometry)

def smacof_mds(C, dim, max_iter=3000, eps=1e-9):
    """
    Returns an interpolated point cloud following the dissimilarity matrix C
    using SMACOF multidimensional scaling (MDS) in specific dimensionned
    target space

    Parameters
    ----------
    C : ndarray, shape (ns, ns)
        dissimilarity matrix
    dim : int
          dimension of the targeted space
    max_iter :  int
        Maximum number of iterations of the SMACOF algorithm for a single run
    eps : float
        relative tolerance w.r.t stress to declare converge

    Returns
    -------
    npos : ndarray, shape (R, dim)
           Embedded coordinates of the interpolated point cloud (defined with
           one isometry)
    """

    rng = np.random.RandomState(seed=3)

    mds = manifold.MDS(
        dim,
        max_iter=max_iter,
        eps=1e-9,
        dissimilarity='precomputed',
        n_init=1)
    pos = mds.fit(C).embedding_

    nmds = manifold.MDS(
        2,
        max_iter=max_iter,
        eps=1e-9,
        dissimilarity="precomputed",
        random_state=rng,
        n_init=1)
    npos = nmds.fit_transform(C, init=pos)

    return npos