Exemplo n.º 1
0
    def __init__(self,
                 num_units,
                 alpha,
                 sigma_rec=0,
                 activation='softplus',
                 w_rec_init='diag',
                 rng=None,
                 reuse=None,
                 name=None):
        super(LeakyRNNCellSeparateInput, self).__init__(_reuse=reuse,
                                                        name=name)

        # Inputs must be 2-dimensional.
        # self.input_spec = base_layer.InputSpec(ndim=2)

        self._num_units = num_units
        self._w_rec_init = w_rec_init
        self._reuse = reuse

        if activation == 'softplus':
            self._activation = tf.nn.softplus
            self._w_in_start = 1.0
            self._w_rec_start = 0.5
        elif activation == 'relu':
            self._activation = tf.nn.relu
            self._w_in_start = 1.0
            self._w_rec_start = 0.5
        else:
            raise ValueError('Unknown activation')
        self._alpha = alpha
        self._sigma = np.sqrt(2 / alpha) * sigma_rec
        if rng is None:
            self.rng = np.random.RandomState()
        else:
            self.rng = rng

        # Generate initialization matrix
        n_hidden = self._num_units

        if self._w_rec_init == 'diag':
            w_rec0 = self._w_rec_start * np.eye(n_hidden)
        elif self._w_rec_init == 'randortho':
            w_rec0 = self._w_rec_start * tools.gen_ortho_matrix(n_hidden,
                                                                rng=self.rng)
        elif self._w_rec_init == 'randgauss':
            w_rec0 = (self._w_rec_start * self.rng.randn(n_hidden, n_hidden) /
                      np.sqrt(n_hidden))
        else:
            raise ValueError

        self.w_rnn0 = w_rec0
        self._initializer = tf.constant_initializer(w_rec0, dtype=tf.float32)
Exemplo n.º 2
0
    def __init__(self,
                 num_units,
                 n_input,
                 alpha,
                 sigma_rec=0,
                 activation='softplus',
                 w_rec_init='diag',
                 rng=None,
                 reuse=None,
                 name=None):
        super(LeakyRNNCell, self).__init__(_reuse=reuse, name=name)

        # Inputs must be 2-dimensional.
        # self.input_spec = base_layer.InputSpec(ndim=2)

        self._num_units = num_units
        self._w_rec_init = w_rec_init
        self._reuse = reuse

        if activation == 'softplus':
            self._activation = lambda x: F.softplus(x)
            self._w_in_start = 1.0
            self._w_rec_start = 0.5
        elif activation == 'tanh':
            self._activation = lambda x: F.tanh(x)
            self._w_in_start = 1.0
            self._w_rec_start = 1.0
        elif activation == 'relu':
            self._activation = lambda x: F.relu(x)
            self._w_in_start = 1.0
            self._w_rec_start = 0.5
        elif activation == 'power':
            self._activation = lambda x: torch.square(F.relu(x))
            self._w_in_start = 1.0
            self._w_rec_start = 0.01
        elif activation == 'retanh':
            self._activation = lambda x: F.tanh(F.relu(x))
            self._w_in_start = 1.0
            self._w_rec_start = 0.5
        else:
            raise ValueError('Unknown activation')
        self._alpha = alpha
        self._sigma = np.sqrt(2 / alpha) * sigma_rec
        if rng is None:
            self.rng = np.random.RandomState()
        else:
            self.rng = rng

        # Generate initialization matrix
        n_hidden = self._num_units
        w_in0 = (self.rng.randn(n_input, n_hidden) / np.sqrt(n_input) *
                 self._w_in_start)

        if self._w_rec_init == 'diag':
            w_rec0 = self._w_rec_start * np.eye(n_hidden)
        elif self._w_rec_init == 'randortho':
            w_rec0 = self._w_rec_start * tools.gen_ortho_matrix(n_hidden,
                                                                rng=self.rng)
        elif self._w_rec_init == 'randgauss':
            w_rec0 = (self._w_rec_start * self.rng.randn(n_hidden, n_hidden) /
                      np.sqrt(n_hidden))

        matrix0 = np.concatenate((w_in0, w_rec0), axis=0)

        self.w_rnn0 = matrix0
        nn.init.constant_(self._initializer, matrix0, dtype=torch.float32)