layers.py 文件源码

def _compute_states(self):

    _inputs = tf.transpose(self.inputs, [1, 0, 2])
    x_ta = tf.TensorArray(tf.float32, size=self.length).unstack(_inputs)
    h_ta = tf.TensorArray(tf.float32, size=self.length)
    c_ta = tf.TensorArray(tf.float32, size=self.length)

    def cond(t, c, h, c_ta, h_ta):
      return tf.less(t, self.length)

    def body(t, c, h, c_ta, h_ta):

      x = x_ta.read(t)
      num_units, input_size = self.num_hidden_units, self.input_size

      with tf.variable_scope('lstm'):
        c_tilde = self.activation(self._linear(h, x, num_units, scope='c'))
        i = tf.nn.sigmoid(self._linear(h, x, num_units, scope='i'))
        f = tf.nn.sigmoid(self._linear(h, x, num_units, shift=self.optional_bias_shift, scope='f'))
        o = tf.nn.sigmoid(self._linear(h, x, num_units, scope='o'))
        c_new = i * c_tilde + f * c
        h_new = o * self.activation(c_new)

      c_ta_new = c_ta.write(t, c_new)
      h_ta_new = h_ta.write(t, h_new)
      return t + 1, c_new, h_new, c_ta_new, h_ta_new

    t = tf.constant(0)
    c, h = tf.split(tf.squeeze(self.initial_states, [1]), 2, axis=1)
    _, _, _, c_ta, h_ta = tf.while_loop(cond, body, [t, c, h, c_ta, h_ta])

    outputs = tf.transpose(h_ta.stack(), [1, 0, 2], name='outputs')
    cells = tf.transpose(c_ta.stack(), [1, 0, 2])
    states = tf.concat([cells, outputs], axis=2, name='states')
    return outputs, states