Exemple #1
0
    def __init__(self, **kwargs):
        self.conf = kwargs

        self.REncoder = None
        self.bias = True
        self.W_i = None
        self.N_i = None
        self.N_o = None
        self.N_f = 0
        self.beta = 1e-6
        self.method = 'ridge'

        self.skip_con = kwargs.get('skip_con', 0)
        self.N_h = 0
        self.reservoirConf = kwargs.get('reservoirConf')
        self.REncoder = ReservoirEncoder(self.reservoirConf)
        self.encoder_func = self.REncoder.echostate \
            if kwargs.get('encoder', 'echostate') == 'echostate' \
            else self.REncoder.transform
Exemple #2
0
    def __init__(self, **kwargs):
        self.conf = kwargs

        self.sigmas = None
        self.bias = True
        self.W_i = None
        self.N_i = None
        self.N_o = None
        self.N_f = 0
        self.beta = 1e-6
        self.method = 'ridge'
        self.skip_con = kwargs.get('skip_con', 0)
        self.activation = kwargs.get('activation', 'rbf')
        self.N_h = kwargs.get('N_h')
        self.sigma = kwargs.get('sigma', 1)
        self.reservoirConf = kwargs.get('reservoirConf')
        self.REncoder = ReservoirEncoder(self.reservoirConf)
        self.encoder_func = self.REncoder.transform \
            if kwargs.get('encoder', 'transform') == 'transform' \
            else self.REncoder.echostate
Exemple #3
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class ESN_ATTN_simple:

    def __init__(self, **kwargs):
        self.conf = kwargs

        self.sigmas = None
        self.bias = True
        self.W_i = None
        self.N_i = None
        self.N_o = None
        self.N_f = 0
        self.beta = 1e-6
        self.method = 'ridge'
        self.skip_con = kwargs.get('skip_con', 0)
        self.activation = kwargs.get('activation', 'rbf')
        self.N_h = kwargs.get('N_h')
        self.sigma = kwargs.get('sigma', 1)
        self.reservoirConf = kwargs.get('reservoirConf')
        self.REncoder = ReservoirEncoder(self.reservoirConf)
        self.encoder_func = self.REncoder.transform \
            if kwargs.get('encoder', 'transform') == 'transform' \
            else self.REncoder.echostate


    @staticmethod
    def pairwise_distances(X, Y):
        D = -2 * X @ Y.T + np.sum(Y ** 2, axis=1) + np.sum(X ** 2, axis=1)[:, np.newaxis]
        D[D < 0] = 0
        return D

    @staticmethod
    def col_normalize(x, f=None):
        if x.shape[0] == 0:
            return x

        fx = f(x) if f else x
        fx_sum = fx.sum(axis=0).reshape([1, fx.shape[1]])
        return fx / fx_sum

    def _pre_output(self, X, Z=None):
        """

        :param X: (N_i, N_samples)
        :param Z: (nz, N_samples)
        :param W_i: ((N_h, nz)
        :return: H: (..., N_samples)
        """
        assert(self.N_h > 0)


        H = np.exp(
            -self.pairwise_distances(self.W_i, Z.T) /
            (2 * self.sigma ** 2 * self.sigmas.reshape((-1, 1)))
        )  # (N_h, N_samples)

        H = np.vstack([H, Z])

        self.N_f = self.N_h + Z.shape[0]

        if self.skip_con:
            H = np.vstack([H, X[-self.skip_con:]])
            self.N_f += len(X[-self.skip_con:])

        if self.bias:
            ones = np.ones((1, H.shape[1]))
            H = np.vstack([H, ones])
            self.N_f += 1

        return H

    def train(self, X, Y, **kwargs):

        num_prepare = kwargs.get('num_prepare', 0)

        self.N_i = X.shape[0]
        self.N_o = Y.shape[0]

        Z = self.encoder_func(X) if self.REncoder else X
        X, Z = X[:, num_prepare:], Z[:, num_prepare:]

        if self.N_h <= 0:
            self.W_i = np.empty((0, self.N_i))

        else:
            # self.W_i, _ = kmeans2(X.T, self.N_h, minit='points')
            if self.activation == 'rbf':
                if self.W_i is None:
                    self.W_i, self.sigmas = fcm(Z.T, self.N_h)

            elif self.activation == 'rbf-random':
                self.W_i = np.random.uniform(-1, 1, (self.N_h, self.N_i))
                # self.W_i = X.T[np.random.choice(X.shape[1],self.N_h,replace=False)]

        H = self._pre_output(X, Z)

        self.W_o = ridge_regressor(H, Y, self.beta)


    def predict(self, X, **kwargs):
        num_prepare = kwargs.get('num_prepare', 0)
        Z = self.encoder_func(X) if self.REncoder else X
        X, Z = X[:, num_prepare:], Z[:, num_prepare:]
        H = self._pre_output(X, Z)
        return self.W_o.dot(H)

    def predict_multistep(self, X, horizon):
        Y = np.empty((self.N_o * horizon, X.shape[1]))
        Z = np.vstack([X, Y])
        start = X.shape[0]
        Z[start:start + self.N_o, :] = self.predict(X)
        for i in range(1, horizon):
            Z[start + i * self.N_o: start + (i + 1) * self.N_o, :] = self.predict(Z[i * self.N_o: start + i * self.N_o, :])
        return Z[start:, :]

    def predict_multistep_esn(self, X, horizon):
        Y = np.empty((self.N_o * horizon, 1))
        Z = self.encoder_func(X)
        z = Z[:, -1:]
        x = X[:, -1:]
        for i in range(horizon):
            H = self._pre_output(x, z)
            y = self.W_o.dot(H)
            Y[i * self.N_o: (i + 1) * self.N_o] = y
            x = np.vstack([x, y])[-self.N_i:]
            z = self.REncoder.state_transition(z, y)
        return Y
Exemple #4
0
class ESN:
    def __init__(self, **kwargs):
        self.conf = kwargs

        self.REncoder = None
        self.bias = True
        self.W_i = None
        self.N_i = None
        self.N_o = None
        self.N_f = 0
        self.beta = 1e-6
        self.method = 'ridge'

        self.skip_con = kwargs.get('skip_con', 0)
        self.N_h = 0
        self.reservoirConf = kwargs.get('reservoirConf')
        self.REncoder = ReservoirEncoder(self.reservoirConf)
        self.encoder_func = self.REncoder.echostate \
            if kwargs.get('encoder', 'echostate') == 'echostate' \
            else self.REncoder.transform

    def _pre_output(self, X, Z=None):
        """

        :param X: (N_i, N_samples)
        :param Z: (nz, N_samples)
        :param W_i: ((N_h, nz)
        :return: H: (..., N_samples)
        """

        H = Z
        self.N_f = Z.shape[0]

        if self.skip_con:
            H = np.vstack([H, X[-self.skip_con:]])
            self.N_f += len(X[-self.skip_con:])

        if self.bias:
            ones = np.ones((1, H.shape[1]))
            H = np.vstack([H, ones])
            self.N_f += 1

        return H

    def train(self, X, Y, **kwargs):

        num_prepare = kwargs.get('num_prepare', 0)

        self.N_i = X.shape[0]
        self.N_o = Y.shape[0]

        Z = self.encoder_func(X) if self.REncoder else X
        X, Z = X[:, num_prepare:], Z[:, num_prepare:]

        H = self._pre_output(X, Z)

        self.W_o = ridge_regressor(H, Y, self.beta)

    def predict(self, X, **kwargs):
        num_prepare = kwargs.get('num_prepare', 0)
        Z = self.encoder_func(X) if self.REncoder else X
        X, Z = X[:, num_prepare:], Z[:, num_prepare:]

        H = self._pre_output(X, Z)
        return self.W_o.dot(H)

    def predict_multistep(self, X, horizon):
        Y = np.empty((self.N_o * horizon, X.shape[1]))
        Z = np.vstack([X, Y])
        start = X.shape[0]
        Z[start:start + self.N_o, :] = self.predict(X)
        for i in range(1, horizon):
            # print(Z[i * self.N_o: start + i * self.N_o, :])
            Z[start + i * self.N_o:start +
              (i + 1) * self.N_o, :] = self.predict(Z[i * self.N_o:start +
                                                      i * self.N_o, :])
        return Z[start:, :]

    def predict_multistep_esn(self, X, horizon):
        Y = np.empty((self.N_o * horizon, 1))
        Z = self.encoder_func(X)
        z = Z[:, -1:]
        x = X[:, -1:]
        for i in range(horizon):
            H = self._pre_output(x, z)
            y = self.W_o.dot(H)
            Y[i * self.N_o:(i + 1) * self.N_o] = y
            x = np.vstack([x, y])[-self.N_i:]
            z = self.REncoder.state_transition(z, y)
            # print(np.min(z), np.max(z))
        return Y