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ZdS )zRestricted Boltzmann Machine
    N)expit   )BaseEstimator)TransformerMixin)check_random_state)gen_even_slices)safe_sparse_dot)log_logistic)check_is_fittedc               @   s   e Zd ZdZd dddddddd	Zd
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d!ddZdd Zdd Zd"ddZdd ZdS )#BernoulliRBMa  Bernoulli Restricted Boltzmann Machine (RBM).

    A Restricted Boltzmann Machine with binary visible units and
    binary hidden units. Parameters are estimated using Stochastic Maximum
    Likelihood (SML), also known as Persistent Contrastive Divergence (PCD)
    [2].

    The time complexity of this implementation is ``O(d ** 2)`` assuming
    d ~ n_features ~ n_components.

    Read more in the :ref:`User Guide <rbm>`.

    Parameters
    ----------
    n_components : int, default=256
        Number of binary hidden units.

    learning_rate : float, default=0.1
        The learning rate for weight updates. It is *highly* recommended
        to tune this hyper-parameter. Reasonable values are in the
        10**[0., -3.] range.

    batch_size : int, default=10
        Number of examples per minibatch.

    n_iter : int, default=10
        Number of iterations/sweeps over the training dataset to perform
        during training.

    verbose : int, default=0
        The verbosity level. The default, zero, means silent mode. Range
        of values is [0, inf].

    random_state : int, RandomState instance or None, default=None
        Determines random number generation for:

        - Gibbs sampling from visible and hidden layers.

        - Initializing components, sampling from layers during fit.

        - Corrupting the data when scoring samples.

        Pass an int for reproducible results across multiple function calls.
        See :term:`Glossary <random_state>`.

    Attributes
    ----------
    intercept_hidden_ : array-like of shape (n_components,)
        Biases of the hidden units.

    intercept_visible_ : array-like of shape (n_features,)
        Biases of the visible units.

    components_ : array-like of shape (n_components, n_features)
        Weight matrix, where `n_features` is the number of
        visible units and `n_components` is the number of hidden units.

    h_samples_ : array-like of shape (batch_size, n_components)
        Hidden Activation sampled from the model distribution,
        where `batch_size` is the number of examples per minibatch and
        `n_components` is the number of hidden units.

    n_features_in_ : int
        Number of features seen during :term:`fit`.

        .. versionadded:: 0.24

    feature_names_in_ : ndarray of shape (`n_features_in_`,)
        Names of features seen during :term:`fit`. Defined only when `X`
        has feature names that are all strings.

        .. versionadded:: 1.0

    See Also
    --------
    sklearn.neural_network.MLPRegressor : Multi-layer Perceptron regressor.
    sklearn.neural_network.MLPClassifier : Multi-layer Perceptron classifier.
    sklearn.decomposition.PCA : An unsupervised linear dimensionality
        reduction model.

    References
    ----------

    [1] Hinton, G. E., Osindero, S. and Teh, Y. A fast learning algorithm for
        deep belief nets. Neural Computation 18, pp 1527-1554.
        https://www.cs.toronto.edu/~hinton/absps/fastnc.pdf

    [2] Tieleman, T. Training Restricted Boltzmann Machines using
        Approximations to the Likelihood Gradient. International Conference
        on Machine Learning (ICML) 2008

    Examples
    --------

    >>> import numpy as np
    >>> from sklearn.neural_network import BernoulliRBM
    >>> X = np.array([[0, 0, 0], [0, 1, 1], [1, 0, 1], [1, 1, 1]])
    >>> model = BernoulliRBM(n_components=2)
    >>> model.fit(X)
    BernoulliRBM(n_components=2)
       g?
   r   N)learning_rate
batch_sizen_iterverboserandom_statec            C   s(   || _ || _|| _|| _|| _|| _d S )N)n_componentsr   r   r   r   r   )selfr   r   r   r   r   r    r   M/var/www/html/venv/lib/python3.7/site-packages/sklearn/neural_network/_rbm.py__init__   s    
zBernoulliRBM.__init__c             C   s,   t |  | j|ddtjtjfd}| |S )ag  Compute the hidden layer activation probabilities, P(h=1|v=X).

        Parameters
        ----------
        X : {array-like, sparse matrix} of shape (n_samples, n_features)
            The data to be transformed.

        Returns
        -------
        h : ndarray of shape (n_samples, n_components)
            Latent representations of the data.
        csrF)accept_sparseresetdtype)r
   _validate_datanpfloat64float32_mean_hiddens)r   Xr   r   r   	transform   s    zBernoulliRBM.transformc             C   s$   t || jj}|| j7 }t||dS )aL  Computes the probabilities P(h=1|v).

        Parameters
        ----------
        v : ndarray of shape (n_samples, n_features)
            Values of the visible layer.

        Returns
        -------
        h : ndarray of shape (n_samples, n_components)
            Corresponding mean field values for the hidden layer.
        )out)r   components_Tintercept_hidden_r   )r   vpr   r   r   r       s    
zBernoulliRBM._mean_hiddensc             C   s   |  |}|j|jd|k S )a  Sample from the distribution P(h|v).

        Parameters
        ----------
        v : ndarray of shape (n_samples, n_features)
            Values of the visible layer to sample from.

        rng : RandomState instance
            Random number generator to use.

        Returns
        -------
        h : ndarray of shape (n_samples, n_components)
            Values of the hidden layer.
        )size)r    random_sampleshape)r   r'   rngr(   r   r   r   _sample_hiddens   s    
zBernoulliRBM._sample_hiddensc             C   s6   t || j}|| j7 }t||d |j|jd|k S )a  Sample from the distribution P(v|h).

        Parameters
        ----------
        h : ndarray of shape (n_samples, n_components)
            Values of the hidden layer to sample from.

        rng : RandomState instance
            Random number generator to use.

        Returns
        -------
        v : ndarray of shape (n_samples, n_features)
            Values of the visible layer.
        )r#   )r)   )r   dotr$   intercept_visible_r   r*   r+   )r   hr,   r(   r   r   r   _sample_visibles   s    
zBernoulliRBM._sample_visiblesc             C   s2   t || j tdt || jj| j jdd S )aF  Computes the free energy F(v) = - log sum_h exp(-E(v,h)).

        Parameters
        ----------
        v : ndarray of shape (n_samples, n_features)
            Values of the visible layer.

        Returns
        -------
        free_energy : ndarray of shape (n_samples,)
            The value of the free energy.
        r      )axis)r   r/   r   Z	logaddexpr$   r%   r&   sum)r   r'   r   r   r   _free_energy   s    zBernoulliRBM._free_energyc             C   s>   t |  t| dst| j| _| || j}| || j}|S )aT  Perform one Gibbs sampling step.

        Parameters
        ----------
        v : ndarray of shape (n_samples, n_features)
            Values of the visible layer to start from.

        Returns
        -------
        v_new : ndarray of shape (n_samples, n_features)
            Values of the visible layer after one Gibbs step.
        random_state_)r
   hasattrr   r   r6   r-   r1   )r   r'   Zh_v_r   r   r   gibbs   s    
zBernoulliRBM.gibbsc             C   s   t | d }| j|dtj|d}t | ds6t| j| _t | dshtj| jdd| j	|j
d fdd	| _t | d
st| j	| _t | dst|j
d | _t | dst| j| j	f| _| || j dS )a  Fit the model to the partial segment of the data X.

        Parameters
        ----------
        X : ndarray of shape (n_samples, n_features)
            Training data.

        y : array-like of shape (n_samples,) or (n_samples, n_outputs), default=None
            Target values (None for unsupervised transformations).

        Returns
        -------
        self : BernoulliRBM
            The fitted model.
        r$   r   )r   r   r   r6   r   g{Gz?r2   F)orderr&   r/   
h_samples_N)r7   r   r   r   r   r   r6   asarraynormalr   r+   r$   zerosr&   r/   r   r<   _fit)r   r!   yZ
first_passr   r   r   partial_fit  s$    

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zBernoulliRBM.partial_fitc             C   s   |  |}| | j|}|  |}t| j|jd  }t|j|ddj}|t	|j|8 }|  j
|| 7  _
|  j||jdd|jdd  7  _|  j|t|jdd |jdd  7  _d||j|jd|k < t||| _dS )a  Inner fit for one mini-batch.

        Adjust the parameters to maximize the likelihood of v using
        Stochastic Maximum Likelihood (SML).

        Parameters
        ----------
        v_pos : ndarray of shape (n_samples, n_features)
            The data to use for training.

        rng : RandomState instance
            Random number generator to use for sampling.
        r   T)Zdense_output)r3   g      ?)r)   N)r    r1   r<   floatr   r+   r   r%   r   r.   r$   r&   r4   r/   r=   Zsqueezeuniformfloor)r   Zv_posr,   Zh_posZv_negZh_neglrupdater   r   r   r@   ,  s    

&(zBernoulliRBM._fitc       	      C   s   t |  | j|ddd}t| j}t|jd |d|jd |jd f}t	|rd||  d }|tj
|j |f|jd }n| }d||  ||< | |}| |}|jd t||  S )a|  Compute the pseudo-likelihood of X.

        Parameters
        ----------
        X : {array-like, sparse matrix} of shape (n_samples, n_features)
            Values of the visible layer. Must be all-boolean (not checked).

        Returns
        -------
        pseudo_likelihood : ndarray of shape (n_samples,)
            Value of the pseudo-likelihood (proxy for likelihood).

        Notes
        -----
        This method is not deterministic: it computes a quantity called the
        free energy on X, then on a randomly corrupted version of X, and
        returns the log of the logistic function of the difference.
        r   F)r   r   r   r2   )r+   )r
   r   r   r   r   Zaranger+   randintspissparseZ
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*
 

zBernoulliRBM.score_samplesc             C   sN  | j |dtjtjfd}|jd }t| j}tj|dd| j	|jd fd|j
d| _tj| j	|j
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d| _tj| j| j	f|j
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| ||
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t| j|	| | || f  |}qW | S )a  Fit the model to the data X.

        Parameters
        ----------
        X : {array-like, sparse matrix} of shape (n_samples, n_features)
            Training data.

        y : array-like of shape (n_samples,) or (n_samples, n_outputs), default=None
            Target values (None for unsupervised transformations).

        Returns
        -------
        self : BernoulliRBM
            The fitted model.
        r   )r   r   r   g{Gz?r2   r:   )r;   r   )r   )	n_samplesz9[%s] Iteration %d, pseudo-likelihood = %.2f, time = %.2fs) r   r   r   r   r+   r   r   r=   r>   r   r   r$   r?   r&   r/   r   r<   intceilrC   listr   r   timeranger   r@   printtype__name__rP   Zmean)r   r!   rA   rQ   r,   Z	n_batchesZbatch_slicesr   begin	iterationZbatch_sliceendr   r   r   fito  s8    


zBernoulliRBM.fitc             C   s   ddddiS )NZ_xfail_checksz&fails for the decision_function methodz"fails for the score_samples method)Zcheck_methods_subset_invarianceZ%check_methods_sample_order_invariancer   )r   r   r   r   
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   r   r   r   r   r   <module>   s   