Ejemplo n.º 1
0
def test_safe_min():
    msg = ("safe_min is deprecated in version 0.22 and will be removed "
           "in version 0.24.")
    with pytest.warns(FutureWarning, match=msg):
        safe_min(np.ones(10))
Ejemplo n.º 2
0
def non_negative_factorization(lam,
                               N,
                               D,
                               X,
                               W=None,
                               H=None,
                               n_components=None,
                               init='warn',
                               update_H=True,
                               solver='mu',
                               beta_loss='KL',
                               tol=1e-4,
                               max_iter=400,
                               alpha=0.,
                               l1_ratio=0.,
                               regularization=None,
                               random_state=None,
                               verbose=0,
                               shuffle=False):

    X = check_array(X, accept_sparse=('csr', 'csc'), dtype=float)
    check_non_negative(X, "NMF (input X)")
    beta_loss = _check_string_param(solver, regularization, beta_loss, init)

    if safe_min(X) == 0 and beta_loss <= 0:
        raise ValueError("When beta_loss <= 0 and X contains zeros, "
                         "the solver may diverge. Please add small values to "
                         "X, or use a positive beta_loss.")

    n_samples, n_features = X.shape
    if n_components is None:
        n_components = n_features

    if not isinstance(n_components, INTEGER_TYPES) or n_components <= 0:
        raise ValueError("Number of components must be a positive integer;"
                         " got (n_components=%r)" % n_components)
    if not isinstance(max_iter, INTEGER_TYPES) or max_iter < 0:
        raise ValueError("Maximum number of iterations must be a positive "
                         "integer; got (max_iter=%r)" % max_iter)
    if not isinstance(tol, numbers.Number) or tol < 0:
        raise ValueError("Tolerance for stopping criteria must be "
                         "positive; got (tol=%r)" % tol)

    if init == "warn":
        if n_components < n_features:
            warnings.warn(
                "The default value of init will change from "
                "random to None in 0.23 to make it consistent "
                "with decomposition.NMF.", FutureWarning)
        init = "random"

    # check W and H, or initialize them
    if init == 'custom' and update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")
        _check_init(W, (n_samples, n_components), "NMF (input W)")
    elif not update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")

        avg = np.sqrt(X.mean() / n_components)
        W = np.full((n_samples, n_components), avg)

    else:
        W, H = _initialize_nmf(X,
                               n_components,
                               init=init,
                               random_state=random_state)

    l1_reg_W, l1_reg_H, l2_reg_W, l2_reg_H = _compute_regularization(
        alpha, l1_ratio, regularization)

    W, H, n_iter = _fit_multiplicative_update(lam, N, D, X, W, H, beta_loss,
                                              max_iter, tol, l1_reg_W,
                                              l1_reg_H, l2_reg_W, l2_reg_H,
                                              update_H, verbose)

    if n_iter == max_iter and tol > 0:
        warnings.warn(
            "Maximum number of iteration %d reached. Increase it to"
            " improve convergence." % max_iter, ConvergenceWarning)

    return W, H, n_iter
Ejemplo n.º 3
0
def non_negative_factorization(X, W=None, H=None, n_components=None,
                               init='random', update_H=True, solver='cd',
                               beta_loss='frobenius', tol=1e-4,
                               max_iter=200, alpha=0., l1_ratio=0.,
                               regularization=None, random_state=None,
                               verbose=0, shuffle=False):
    """Compute Non-negative Matrix Factorization (NMF)

    Find two non-negative matrices (W, H) whose product approximates the non-
    negative matrix X. This factorization can be used for example for
    dimensionality reduction, source separation or topic extraction.

    The objective function is::

        0.5 * ||X - WH||_Fro^2
        + alpha * l1_ratio * ||vec(W)||_1
        + alpha * l1_ratio * ||vec(H)||_1
        + 0.5 * alpha * (1 - l1_ratio) * ||W||_Fro^2
        + 0.5 * alpha * (1 - l1_ratio) * ||H||_Fro^2

    Where::

        ||A||_Fro^2 = \sum_{i,j} A_{ij}^2 (Frobenius norm)
        ||vec(A)||_1 = \sum_{i,j} abs(A_{ij}) (Elementwise L1 norm)

    For multiplicative-update ('mu') solver, the Frobenius norm
    (0.5 * ||X - WH||_Fro^2) can be changed into another beta-divergence loss,
    by changing the beta_loss parameter.

    The objective function is minimized with an alternating minimization of W
    and H. If H is given and update_H=False, it solves for W only.

    Parameters
    ----------
    X : array-like, shape (n_samples, n_features)
        Constant matrix.

    W : array-like, shape (n_samples, n_components)
        If init='custom', it is used as initial guess for the solution.

    H : array-like, shape (n_components, n_features)
        If init='custom', it is used as initial guess for the solution.
        If update_H=False, it is used as a constant, to solve for W only.

    n_components : integer
        Number of components, if n_components is not set all features
        are kept.

    init :  None | 'random' | 'nndsvd' | 'nndsvda' | 'nndsvdar' | 'custom'
        Method used to initialize the procedure.
        Default: 'nndsvd' if n_components < n_features, otherwise random.
        Valid options:

        - 'random': non-negative random matrices, scaled with:
            sqrt(X.mean() / n_components)

        - 'nndsvd': Nonnegative Double Singular Value Decomposition (NNDSVD)
            initialization (better for sparseness)

        - 'nndsvda': NNDSVD with zeros filled with the average of X
            (better when sparsity is not desired)

        - 'nndsvdar': NNDSVD with zeros filled with small random values
            (generally faster, less accurate alternative to NNDSVDa
            for when sparsity is not desired)

        - 'custom': use custom matrices W and H

    update_H : boolean, default: True
        Set to True, both W and H will be estimated from initial guesses.
        Set to False, only W will be estimated.

    solver : 'cd' | 'mu'
        Numerical solver to use:
        'cd' is a Coordinate Descent solver.
        'mu' is a Multiplicative Update solver.

        .. versionadded:: 0.17
           Coordinate Descent solver.

        .. versionadded:: 0.19
           Multiplicative Update solver.

    beta_loss : float or string, default 'frobenius'
        String must be in {'frobenius', 'kullback-leibler', 'itakura-saito'}.
        Beta divergence to be minimized, measuring the distance between X
        and the dot product WH. Note that values different from 'frobenius'
        (or 2) and 'kullback-leibler' (or 1) lead to significantly slower
        fits. Note that for beta_loss <= 0 (or 'itakura-saito'), the input
        matrix X cannot contain zeros. Used only in 'mu' solver.

        .. versionadded:: 0.19

    tol : float, default: 1e-4
        Tolerance of the stopping condition.

    max_iter : integer, default: 200
        Maximum number of iterations before timing out.

    alpha : double, default: 0.
        Constant that multiplies the regularization terms.

    l1_ratio : double, default: 0.
        The regularization mixing parameter, with 0 <= l1_ratio <= 1.
        For l1_ratio = 0 the penalty is an elementwise L2 penalty
        (aka Frobenius Norm).
        For l1_ratio = 1 it is an elementwise L1 penalty.
        For 0 < l1_ratio < 1, the penalty is a combination of L1 and L2.

    regularization : 'both' | 'components' | 'transformation' | None
        Select whether the regularization affects the components (H), the
        transformation (W), both or none of them.

    random_state : integer seed, RandomState instance, or None (default)
        Random number generator seed control.

    verbose : integer, default: 0
        The verbosity level.

    shuffle : boolean, default: False
        If true, randomize the order of coordinates in the CD solver.

    Returns
    -------
    W : array-like, shape (n_samples, n_components)
        Solution to the non-negative least squares problem.

    H : array-like, shape (n_components, n_features)
        Solution to the non-negative least squares problem.

    n_iter : int
        Actual number of iterations.

    Examples
    --------
    >>> import numpy as np
    >>> X = np.array([[1,1], [2, 1], [3, 1.2], [4, 1], [5, 0.8], [6, 1]])
    >>> from sklearn.decomposition import non_negative_factorization
    >>> W, H, n_iter = non_negative_factorization(X, n_components=2, \
        init='random', random_state=0)

    References
    ----------
    Cichocki, Andrzej, and P. H. A. N. Anh-Huy. "Fast local algorithms for
    large scale nonnegative matrix and tensor factorizations."
    IEICE transactions on fundamentals of electronics, communications and
    computer sciences 92.3: 708-721, 2009.

    Fevotte, C., & Idier, J. (2011). Algorithms for nonnegative matrix
    factorization with the beta-divergence. Neural Computation, 23(9).
    """

    X = check_array(X, accept_sparse=('csr', 'csc'), force_all_finite=False)
    check_non_negative(X, "NMF (input X)", accept_nan=True)
    beta_loss = _check_string_param(solver, regularization, beta_loss, init)

    if sp.issparse(X) and np.any(np.isnan(X.data)):
        raise ValueError("X contains NaN values, and NMF with missing "
                         "values is not implemented for sparse matrices.")

    if not sp.issparse(X) and np.any(np.isnan(X)) and solver != 'mu':
        raise ValueError("NMF solver '%s' cannot handle missing values. "
                         "Use 'mu' solver or remove NaN from the input X."
                         % solver)

    if safe_min(X) == 0 and beta_loss <= 0:
        raise ValueError("When beta_loss <= 0 and X contains zeros, "
                         "the solver may diverge. Please add small values to "
                         "X, or use a positive beta_loss.")

    n_samples, n_features = X.shape
    if n_components is None:
        n_components = n_features

    if not isinstance(n_components, INTEGER_TYPES) or n_components <= 0:
        raise ValueError("Number of components must be a positive integer;"
                         " got (n_components=%r)" % n_components)
    if not isinstance(max_iter, INTEGER_TYPES) or max_iter < 0:
        raise ValueError("Maximum number of iterations must be a positive "
                         "integer; got (max_iter=%r)" % max_iter)
    if not isinstance(tol, numbers.Number) or tol < 0:
        raise ValueError("Tolerance for stopping criteria must be "
                         "positive; got (tol=%r)" % tol)

    # check W and H, or initialize them
    if init == 'custom' and update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")
        _check_init(W, (n_samples, n_components), "NMF (input W)")
    elif not update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")
        # 'mu' solver should not be initialized by zeros
        if solver == 'mu':
            avg = np.sqrt(X.mean() / n_components)
            W = avg * np.ones((n_samples, n_components))
        else:
            W = np.zeros((n_samples, n_components))
    else:
        W, H = _initialize_nmf(X, n_components, init=init,
                               random_state=random_state)

    l1_reg_W, l1_reg_H, l2_reg_W, l2_reg_H = _compute_regularization(
        alpha, l1_ratio, regularization)

    if solver == 'cd':
        W, H, n_iter = _fit_coordinate_descent(X, W, H, tol, max_iter,
                                               l1_reg_W, l1_reg_H,
                                               l2_reg_W, l2_reg_H,
                                               update_H=update_H,
                                               verbose=verbose,
                                               shuffle=shuffle,
                                               random_state=random_state)
    elif solver == 'mu':
        W, H, n_iter = _fit_multiplicative_update(X, W, H, beta_loss, max_iter,
                                                  tol, l1_reg_W, l1_reg_H,
                                                  l2_reg_W, l2_reg_H, update_H,
                                                  verbose)

    else:
        raise ValueError("Invalid solver parameter '%s'." % solver)

    if n_iter == max_iter and tol > 0:
        warnings.warn("Maximum number of iteration %d reached. Increase it to"
                      " improve convergence." % max_iter, ConvergenceWarning)

    return W, H, n_iter
def non_negative_factorization(X, W=None, H=None, n_components=None,
                               init='random', update_H=True, solver='cd',
                               beta_loss='frobenius', tol=1e-4,
                               max_iter=200, alpha=0., l1_ratio=0.,
                               regularization=None, random_state=None,
                               verbose=0, shuffle=False, distribution = 'gaussian', N=None, D=None):
    r"""Compute Non-negative Matrix Factorization (NMF)
    Find two non-negative matrices (W, H) whose product approximates the non-
    negative matrix X. This factorization can be used for example for
    dimensionality reduction, source separation or topic extraction.
    The objective function is::
        0.5 * ||X - WH||_Fro^2
        + alpha * l1_ratio * ||vec(W)||_1
        + alpha * l1_ratio * ||vec(H)||_1
        + 0.5 * alpha * (1 - l1_ratio) * ||W||_Fro^2
        + 0.5 * alpha * (1 - l1_ratio) * ||H||_Fro^2
    Where::
        ||A||_Fro^2 = \sum_{i,j} A_{ij}^2 (Frobenius norm)
        ||vec(A)||_1 = \sum_{i,j} abs(A_{ij}) (Elementwise L1 norm)
    For multiplicative-update ('mu') solver, the Frobenius norm
    (0.5 * ||X - WH||_Fro^2) can be changed into another beta-divergence loss,
    by changing the beta_loss parameter.
    The objective function is minimized with an alternating minimization of W
    and H. If H is given and update_H=False, it solves for W only.
    Parameters
    ----------
    X : array-like, shape (n_samples, n_features)
        Constant matrix.
    W : array-like, shape (n_samples, n_components)
        If init='custom', it is used as initial guess for the solution.
    H : array-like, shape (n_components, n_features)
        If init='custom', it is used as initial guess for the solution.
        If update_H=False, it is used as a constant, to solve for W only.
    n_components : integer
        Number of components, if n_components is not set all features
        are kept.
    init :  None | 'random' | 'nndsvd' | 'nndsvda' | 'nndsvdar' | 'custom'
        Method used to initialize the procedure.
        Default: 'random'.
        Valid options:
        - 'random': non-negative random matrices, scaled with:
            sqrt(X.mean() / n_components)
        - 'nndsvd': Nonnegative Double Singular Value Decomposition (NNDSVD)
            initialization (better for sparseness)
        - 'nndsvda': NNDSVD with zeros filled with the average of X
            (better when sparsity is not desired)
        - 'nndsvdar': NNDSVD with zeros filled with small random values
            (generally faster, less accurate alternative to NNDSVDa
            for when sparsity is not desired)
        - 'custom': use custom matrices W and H
    update_H : boolean, default: True
        Set to True, both W and H will be estimated from initial guesses.
        Set to False, only W will be estimated.
    solver : 'cd' | 'mu'
        Numerical solver to use:
        'cd' is a Coordinate Descent solver that uses Fast Hierarchical
            Alternating Least Squares (Fast HALS).
        'mu' is a Multiplicative Update solver.
        .. versionadded:: 0.17
           Coordinate Descent solver.
        .. versionadded:: 0.19
           Multiplicative Update solver.
    beta_loss : float or string, default 'frobenius'
        String must be in {'frobenius', 'kullback-leibler', 'itakura-saito'}.
        Beta divergence to be minimized, measuring the distance between X
        and the dot product WH. Note that values different from 'frobenius'
        (or 2) and 'kullback-leibler' (or 1) lead to significantly slower
        fits. Note that for beta_loss <= 0 (or 'itakura-saito'), the input
        matrix X cannot contain zeros. Used only in 'mu' solver.
        .. versionadded:: 0.19
    tol : float, default: 1e-4
        Tolerance of the stopping condition.
    max_iter : integer, default: 200
        Maximum number of iterations before timing out.
    alpha : double, default: 0.
        Constant that multiplies the regularization terms.
    l1_ratio : double, default: 0.
        The regularization mixing parameter, with 0 <= l1_ratio <= 1.
        For l1_ratio = 0 the penalty is an elementwise L2 penalty
        (aka Frobenius Norm).
        For l1_ratio = 1 it is an elementwise L1 penalty.
        For 0 < l1_ratio < 1, the penalty is a combination of L1 and L2.
    regularization : 'both' | 'components' | 'transformation' | None
        Select whether the regularization affects the components (H), the
        transformation (W), both or none of them.
    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`.
    verbose : integer, default: 0
        The verbosity level.
    shuffle : boolean, default: False
        If true, randomize the order of coordinates in the CD solver.
    Returns
    -------
    W : array-like, shape (n_samples, n_components)
        Solution to the non-negative least squares problem.
    H : array-like, shape (n_components, n_features)
        Solution to the non-negative least squares problem.
    n_iter : int
        Actual number of iterations.
    Examples
    --------
    >>> import numpy as np
    >>> X = np.array([[1,1], [2, 1], [3, 1.2], [4, 1], [5, 0.8], [6, 1]])
    >>> from sklearn.decomposition import non_negative_factorization
    >>> W, H, n_iter = non_negative_factorization(X, n_components=2,
    ... init='random', random_state=0)
    References
    ----------
    Cichocki, Andrzej, and P. H. A. N. Anh-Huy. "Fast local algorithms for
    large scale nonnegative matrix and tensor factorizations."
    IEICE transactions on fundamentals of electronics, communications and
    computer sciences 92.3: 708-721, 2009.
    Fevotte, C., & Idier, J. (2011). Algorithms for nonnegative matrix
    factorization with the beta-divergence. Neural Computation, 23(9).
    """

    #print('My Non negative Factorization')

    X = check_array(X, accept_sparse=('csr', 'csc'), dtype=float)
    check_non_negative(X, "NMF (input X)")
    beta_loss = _check_string_param(solver, regularization, beta_loss, init)

    if safe_min(X) == 0 and beta_loss <= 0:
        raise ValueError("When beta_loss <= 0 and X contains zeros, "
                         "the solver may diverge. Please add small values to "
                         "X, or use a positive beta_loss.")

    n_samples, n_features = X.shape
    if n_components is None:
        n_components = n_features

    if not isinstance(n_components, INTEGER_TYPES) or n_components <= 0:
        raise ValueError("Number of components must be a positive integer;"
                         " got (n_components=%r)" % n_components)
    if not isinstance(max_iter, INTEGER_TYPES) or max_iter < 0:
        raise ValueError("Maximum number of iterations must be a positive "
                         "integer; got (max_iter=%r)" % max_iter)
    if not isinstance(tol, numbers.Number) or tol < 0:
        raise ValueError("Tolerance for stopping criteria must be "
                         "positive; got (tol=%r)" % tol)

    # check W and H, or initialize them
    if init == 'custom' and update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")
        _check_init(W, (n_samples, n_components), "NMF (input W)")
    elif not update_H:
        _check_init(H, (n_components, n_features), "NMF (input H)")
        # 'mu' solver should not be initialized by zeros
        if solver == 'mu':
            avg = np.sqrt(X.mean() / n_components)
            W = np.full((n_samples, n_components), avg)
        else:
            W = np.zeros((n_samples, n_components))
    else:
        W, H = _initialize_nmf(X, n_components, init=init,
                               random_state=random_state)


    l1_reg_W, l1_reg_H, l2_reg_W, l2_reg_H = _compute_regularization(
        alpha, l1_ratio, regularization)

    W, H, n_iter = update(X, W, H, max_iter, distribution, N , D)


    if n_iter == max_iter and tol > 0:
        warnings.warn("Maximum number of iteration %d reached. Increase it to"
                      " improve convergence." % max_iter, ConvergenceWarning)

    return W, H, n_iter