frame_level_models.py 文件源码

def sub_moe(self,
                model_input,
                vocab_size,
                num_mixtures = None,
                l2_penalty=1e-8,
                scopename="",
                **unused_params):

        num_mixtures = num_mixtures or FLAGS.moe_num_mixtures

        gate_activations = slim.fully_connected(
            model_input,
            vocab_size * (num_mixtures + 1),
            activation_fn=None,
            biases_initializer=None,
            weights_regularizer=slim.l2_regularizer(l2_penalty),
            scope="gates"+scopename)
        expert_activations = slim.fully_connected(
            model_input,
            vocab_size * num_mixtures,
            activation_fn=None,
            weights_regularizer=slim.l2_regularizer(l2_penalty),
            scope="experts"+scopename)

        gating_distribution = tf.nn.softmax(tf.reshape(
            gate_activations,
            [-1, num_mixtures + 1]))  # (Batch * #Labels) x (num_mixtures + 1)
        expert_distribution = tf.nn.sigmoid(tf.reshape(
            expert_activations,
            [-1, num_mixtures]))  # (Batch * #Labels) x num_mixtures


        final_probabilities_by_class_and_batch = tf.reduce_sum(
            gating_distribution[:, :num_mixtures] * expert_distribution, 1)

        final_probabilities = tf.reshape(final_probabilities_by_class_and_batch,
                                         [-1, vocab_size])
        return model_input, final_probabilities