Locally Linear Embedding
Read more in the :ref:`User Guide <locally_linear_embedding>`.
Parameters ---------- n_neighbors : integer number of neighbors to consider for each point.
n_components : integer number of coordinates for the manifold
reg : float regularization constant, multiplies the trace of the local covariance matrix of the distances.
eigen_solver : string, 'auto', 'arpack', 'dense'
auto : algorithm will attempt to choose the best method for input data
arpack : use arnoldi iteration in shift-invert mode. For this method, M may be a dense matrix, sparse matrix, or general linear operator. Warning: ARPACK can be unstable for some problems. It is best to try several random seeds in order to check results.
dense : use standard dense matrix operations for the eigenvalue decomposition. For this method, M must be an array or matrix type. This method should be avoided for large problems.
tol : float, optional Tolerance for 'arpack' method Not used if eigen_solver=='dense'.
max_iter : integer maximum number of iterations for the arpack solver. Not used if eigen_solver=='dense'.
method : string ('standard', 'hessian', 'modified' or 'ltsa') standard : use the standard locally linear embedding algorithm. see reference 1
hessian : use the Hessian eigenmap method. This method requires ``n_neighbors > n_components * (1 + (n_components + 1) / 2`` see reference 2
modified : use the modified locally linear embedding algorithm. see reference 3
ltsa : use local tangent space alignment algorithm see reference 4
hessian_tol : float, optional Tolerance for Hessian eigenmapping method. Only used if ``method == 'hessian'``
modified_tol : float, optional Tolerance for modified LLE method. Only used if ``method == 'modified'``
neighbors_algorithm : string 'auto'|'brute'|'kd_tree'|'ball_tree'
algorithm to use for nearest neighbors search, passed to neighbors.NearestNeighbors instance
random_state : int, RandomState instance or None, optional (default=None) If int, random_state is the seed used by the random number generator; If RandomState instance, random_state is the random number generator; If None, the random number generator is the RandomState instance used by `np.random`. Used when ``eigen_solver`` == 'arpack'.
n_jobs : int or None, optional (default=None) The number of parallel jobs to run. ``None`` means 1 unless in a :obj:`joblib.parallel_backend` context. ``-1`` means using all processors. See :term:`Glossary <n_jobs>` for more details.
Attributes ---------- embedding_ : array-like, shape n_samples, n_components
Stores the embedding vectors
reconstruction_error_ : float Reconstruction error associated with `embedding_`
nbrs_ : NearestNeighbors object Stores nearest neighbors instance, including BallTree or KDtree if applicable.
Examples -------- >>> from sklearn.datasets import load_digits >>> from sklearn.manifold import LocallyLinearEmbedding >>> X, _ = load_digits(return_X_y=True) >>> X.shape (1797, 64) >>> embedding = LocallyLinearEmbedding(n_components=2) >>> X_transformed = embedding.fit_transform(X:100
) >>> X_transformed.shape (100, 2)
References ----------
.. 1
Roweis, S. & Saul, L. Nonlinear dimensionality reduction by locally linear embedding. Science 290:2323 (2000). .. 2
Donoho, D. & Grimes, C. Hessian eigenmaps: Locally linear embedding techniques for high-dimensional data. Proc Natl Acad Sci U S A. 100:5591 (2003). .. 3
Zhang, Z. & Wang, J. MLLE: Modified Locally Linear Embedding Using Multiple Weights. http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.70.382 .. 4
Zhang, Z. & Zha, H. Principal manifolds and nonlinear dimensionality reduction via tangent space alignment. Journal of Shanghai Univ. 8:406 (2004)