Пример #1
0
    def __init__(
            self,
            manager_optimizer=None,
            optimizer=None,
            snn_optimizer=None,
            optimizer_args=None,
            step_size=1e-6,
            latents=None,  # some sort of iterable of the actual latent vectors
            period=10,  # how often I choose a latent
            truncate_local_is_ratio=None,
            **kwargs):
        if optimizer is None:
            if optimizer_args is None:
                # optimizer_args = dict()
                optimizer_args = dict(batch_size=None)
            self.optimizer = FirstOrderOptimizer(
                learning_rate=step_size,
                **optimizer_args)  # I hope this is right
        self.manager_optimizer = manager_optimizer
        self.snn_optimizer = snn_optimizer
        self.step_size = step_size
        self.truncate_local_is_ratio = truncate_local_is_ratio
        super(PG_concurrent,
              self).__init__(**kwargs)  # not sure if this line is correct
        self.latents = latents
        self.period = period

        # todo: fix this sampler stuff
        self.sampler = HierBatchSampler(self, self.period)

        # i hope this is right
        self.diagonal = DiagonalGaussian(
            self.policy.low_policy.action_space.flat_dim)
        self.debug_fns = []
    def __init__(self,
                 optimizer=None,
                 optimizer_args=None,
                 step_size=0.003,
                 num_latents=6,
                 latents=None,  # some sort of iterable of the actual latent vectors
                 period=10,  # how often I choose a latent
                 truncate_local_is_ratio=None,
                 epsilon=0.1,
                 train_pi_iters=10,
                 use_skill_dependent_baseline=False,
                 mlp_skill_dependent_baseline=False,
                 freeze_manager=False,
                 freeze_skills=False,
                 **kwargs):
        if optimizer is None:
            if optimizer_args is None:
                # optimizer_args = dict()
                optimizer_args = dict(batch_size=None)
            self.optimizer = FirstOrderOptimizer(learning_rate=step_size, max_epochs=train_pi_iters, **optimizer_args)
        self.step_size = step_size
        self.truncate_local_is_ratio = truncate_local_is_ratio
        self.epsilon = epsilon

        super(Concurrent_PPO, self).__init__(**kwargs)  # not sure if this line is correct
        self.num_latents = kwargs['policy'].latent_dim
        self.latents = latents
        self.period = period
        self.freeze_manager = freeze_manager
        self.freeze_skills = freeze_skills
        assert (not freeze_manager) or (not freeze_skills)

        # todo: fix this sampler stuff
        # import pdb; pdb.set_trace()
        self.sampler = HierBatchSampler(self, self.period)
        # self.sampler = BatchSampler(self)
        # i hope this is right
        self.diagonal = DiagonalGaussian(self.policy.low_policy.action_space.flat_dim)
        self.debug_fns = []

        assert isinstance(self.policy, HierarchicalPolicy)
        if self.policy is not None:
            self.period = self.policy.period
        assert self.policy.period == self.period
        # self.old_policy = copy.deepcopy(self.policy)

        # skill dependent baseline
        self.use_skill_dependent_baseline = use_skill_dependent_baseline
        self.mlp_skill_dependent_baseline = mlp_skill_dependent_baseline
        if use_skill_dependent_baseline:
            curr_env = kwargs['env']
            skill_dependent_action_space = curr_env.action_space
            new_obs_space_no_bi = curr_env.observation_space.shape[0] + 1  # 1 for the t_remaining
            skill_dependent_obs_space_dim = (new_obs_space_no_bi * (self.num_latents + 1) + self.num_latents,)
            skill_dependent_obs_space = Box(-1.0, 1.0, shape=skill_dependent_obs_space_dim)
            skill_dependent_env_spec = EnvSpec(skill_dependent_obs_space, skill_dependent_action_space)
            if self.mlp_skill_dependent_baseline:
                self.skill_dependent_baseline = GaussianMLPBaseline(env_spec=skill_dependent_env_spec)
            else:
                self.skill_dependent_baseline = LinearFeatureBaseline(env_spec=skill_dependent_env_spec)
    def __init__(
            self,
            optimizer=None,
            optimizer_args=None,
            step_size=1e-2,
            num_latents=6,
            latents=None,  # some sort of iterable of the actual latent vectors
            period=10,  # how often I choose a latent
            truncate_local_is_ratio=None,
            use_skill_dependent_baseline=False,
            **kwargs):
        Serializable.quick_init(self, locals())
        if optimizer is None:
            default_args = dict(batch_size=None, max_epochs=1)
            if optimizer_args is None:
                optimizer_args = default_args
            else:
                optimizer_args = dict(default_args, **optimizer_args)
            optimizer = FirstOrderOptimizer(learning_rate=step_size,
                                            **optimizer_args)
        self.optimizer = optimizer
        self.step_size = step_size
        self.truncate_local_is_ratio = truncate_local_is_ratio
        super(PG_concurrent_approx,
              self).__init__(**kwargs)  # not sure if this line is correct
        self.num_latents = kwargs['policy'].latent_dim
        self.latents = latents
        self.period = period

        # todo: fix this sampler stuff
        self.sampler = HierBatchSampler(self, self.period)

        # i hope this is right
        self.diagonal = DiagonalGaussian(
            self.policy.low_policy.action_space.flat_dim)
        self.debug_fns = []

        assert isinstance(self.policy, HierarchicalPolicy)
        if self.policy is not None:
            self.period = self.policy.period
        assert self.policy.period == self.period

        self.trainable_manager = self.policy.trainable_manager

        # skill dependent baseline
        self.use_skill_dependent_baseline = use_skill_dependent_baseline
        if use_skill_dependent_baseline:
            curr_env = kwargs['env']
            skill_dependent_action_space = curr_env.action_space
            skill_dependent_obs_space_dim = (
                (curr_env.observation_space.shape[0] + 1) * self.num_latents, )
            skill_dependent_obs_space = Box(
                -1.0, 1.0, shape=skill_dependent_obs_space_dim)
            skill_depdendent_env_spec = EnvSpec(skill_dependent_obs_space,
                                                skill_dependent_action_space)
            self.skill_dependent_baseline = LinearFeatureBaseline(
                env_spec=skill_depdendent_env_spec)
Пример #4
0
    def __init__(
            self,
            optimizer=None,
            optimizer_args=None,
            step_size=0.0003,
            latents=None,  # some sort of iterable of the actual latent vectors
            average_period=10,  # average over all the periods
            truncate_local_is_ratio=None,
            epsilon=0.1,
            train_pi_iters=80,
            use_skill_dependent_baseline=False,
            **kwargs):
        if optimizer is None:
            if optimizer_args is None:
                # optimizer_args = dict()
                optimizer_args = dict(batch_size=None)
            self.optimizer = FirstOrderOptimizer(learning_rate=step_size,
                                                 max_epochs=train_pi_iters,
                                                 **optimizer_args)
        self.step_size = step_size
        self.truncate_local_is_ratio = truncate_local_is_ratio
        self.epsilon = epsilon

        super(Hippo,
              self).__init__(**kwargs)  # not sure if this line is correct
        self.num_latents = kwargs['policy'].latent_dim
        self.latents = latents
        self.average_period = average_period

        # import pdb; pdb.set_trace()
        self.sampler = BatchSampler(self)

        # i hope this is right
        self.diagonal = DiagonalGaussian(
            self.policy.low_policy.action_space.flat_dim)
        self.debug_fns = []
        self.use_skill_dependent_baseline = use_skill_dependent_baseline

        assert isinstance(self.policy, HierarchicalPolicy)
        self.old_policy = copy.deepcopy(self.policy)
Пример #5
0
    def __init__(
        self,
        input_shape,
        output_dim,
        mean_network=None,
        hidden_sizes=(32, 32),
        hidden_nonlinearity=NL.rectify,
        optimizer=None,
        use_trust_region=True,
        step_size=0.01,
        learn_std=True,
        init_std=1.0,
        adaptive_std=False,
        std_share_network=False,
        std_hidden_sizes=(32, 32),
        std_nonlinearity=None,
        normalize_inputs=True,
        normalize_outputs=True,
        name=None,
    ):
        """
        :param input_shape: Shape of the input data.
        :param output_dim: Dimension of output.
        :param hidden_sizes: Number of hidden units of each layer of the mean network.
        :param hidden_nonlinearity: Non-linearity used for each layer of the mean network.
        :param optimizer: Optimizer for minimizing the negative log-likelihood.
        :param use_trust_region: Whether to use trust region constraint.
        :param step_size: KL divergence constraint for each iteration
        :param learn_std: Whether to learn the standard deviations. Only effective if adaptive_std is False. If
        adaptive_std is True, this parameter is ignored, and the weights for the std network are always learned.
        :param adaptive_std: Whether to make the std a function of the states.
        :param std_share_network: Whether to use the same network as the mean.
        :param std_hidden_sizes: Number of hidden units of each layer of the std network. Only used if
        `std_share_network` is False. It defaults to the same architecture as the mean.
        :param std_nonlinearity: Non-linearity used for each layer of the std network. Only used if `std_share_network`
        is False. It defaults to the same non-linearity as the mean.
        """
        Serializable.quick_init(self, locals())

        if optimizer is None:
            if use_trust_region:
                optimizer = PenaltyLbfgsOptimizer()
            else:
                optimizer = LbfgsOptimizer()

        self._optimizer = optimizer

        if mean_network is None:
            mean_network = MLP(
                input_shape=input_shape,
                output_dim=output_dim,
                hidden_sizes=hidden_sizes,
                hidden_nonlinearity=hidden_nonlinearity,
                output_nonlinearity=None,
            )

        l_mean = mean_network.output_layer

        if adaptive_std:
            l_log_std = MLP(
                input_shape=input_shape,
                input_var=mean_network.input_layer.input_var,
                output_dim=output_dim,
                hidden_sizes=std_hidden_sizes,
                hidden_nonlinearity=std_nonlinearity,
                output_nonlinearity=None,
            ).output_layer
        else:
            l_log_std = ParamLayer(
                mean_network.input_layer,
                num_units=output_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std",
                trainable=learn_std,
            )

        LasagnePowered.__init__(self, [l_mean, l_log_std])

        xs_var = mean_network.input_layer.input_var
        ys_var = TT.matrix("ys")
        old_means_var = TT.matrix("old_means")
        old_log_stds_var = TT.matrix("old_log_stds")

        x_mean_var = theano.shared(np.zeros((1, ) + input_shape),
                                   name="x_mean",
                                   broadcastable=(True, ) +
                                   (False, ) * len(input_shape))
        x_std_var = theano.shared(np.ones((1, ) + input_shape),
                                  name="x_std",
                                  broadcastable=(True, ) +
                                  (False, ) * len(input_shape))
        y_mean_var = theano.shared(np.zeros((1, output_dim)),
                                   name="y_mean",
                                   broadcastable=(True, False))
        y_std_var = theano.shared(np.ones((1, output_dim)),
                                  name="y_std",
                                  broadcastable=(True, False))

        normalized_xs_var = (xs_var - x_mean_var) / x_std_var
        normalized_ys_var = (ys_var - y_mean_var) / y_std_var

        normalized_means_var = L.get_output(
            l_mean, {mean_network.input_layer: normalized_xs_var})
        normalized_log_stds_var = L.get_output(
            l_log_std, {mean_network.input_layer: normalized_xs_var})

        means_var = normalized_means_var * y_std_var + y_mean_var
        log_stds_var = normalized_log_stds_var + TT.log(y_std_var)

        normalized_old_means_var = (old_means_var - y_mean_var) / y_std_var
        normalized_old_log_stds_var = old_log_stds_var - TT.log(y_std_var)

        dist = self._dist = DiagonalGaussian()

        normalized_dist_info_vars = dict(mean=normalized_means_var,
                                         log_std=normalized_log_stds_var)

        mean_kl = TT.mean(
            dist.kl_sym(
                dict(mean=normalized_old_means_var,
                     log_std=normalized_old_log_stds_var),
                normalized_dist_info_vars,
            ))

        loss = -TT.mean(
            dist.log_likelihood_sym(normalized_ys_var,
                                    normalized_dist_info_vars))

        self._f_predict = compile_function([xs_var], means_var)
        self._f_pdists = compile_function([xs_var], [means_var, log_stds_var])
        self._l_mean = l_mean
        self._l_log_std = l_log_std

        optimizer_args = dict(
            loss=loss,
            target=self,
            network_outputs=[normalized_means_var, normalized_log_stds_var],
        )

        if use_trust_region:
            optimizer_args["leq_constraint"] = (mean_kl, step_size)
            optimizer_args["inputs"] = [
                xs_var, ys_var, old_means_var, old_log_stds_var
            ]
        else:
            optimizer_args["inputs"] = [xs_var, ys_var]

        self._optimizer.update_opt(**optimizer_args)

        self._use_trust_region = use_trust_region
        self._name = name

        self._normalize_inputs = normalize_inputs
        self._normalize_outputs = normalize_outputs
        self._x_mean_var = x_mean_var
        self._x_std_var = x_std_var
        self._y_mean_var = y_mean_var
        self._y_std_var = y_std_var
Пример #6
0
    def __init__(
        self,
        env_spec,
        hidden_sizes=(32, 32),
        learn_std=True,
        init_std=1.0,
        adaptive_std=False,
        std_share_network=False,
        std_hidden_sizes=(32, 32),
        min_std=1e-6,
        std_hidden_nonlinearity=NL.tanh,
        hidden_nonlinearity=NL.tanh,
        output_nonlinearity=None,
    ):
        """
        :param env_spec:
        :param hidden_sizes: list of sizes for the fully-connected hidden layers
        :param learn_std: Is std trainable
        :param init_std: Initial std
        :param adaptive_std:
        :param std_share_network:
        :param std_hidden_sizes: list of sizes for the fully-connected layers for std
        :param min_std: whether to make sure that the std is at least some threshold value, to avoid numerical issues
        :param std_hidden_nonlinearity:
        :param hidden_nonlinearity: nonlinearity used for each hidden layer
        :param output_nonlinearity: nonlinearity for the output layer
        :return:
        """
        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        obs_dim = env_spec.observation_space.flat_dim
        action_dim = env_spec.action_space.flat_dim

        # create network
        mean_network = MLP(
            input_shape=(obs_dim, ),
            output_dim=action_dim,
            hidden_sizes=hidden_sizes,
            hidden_nonlinearity=hidden_nonlinearity,
            output_nonlinearity=output_nonlinearity,
        )
        self._mean_network = mean_network

        l_mean = mean_network.output_layer
        obs_var = mean_network.input_var

        if adaptive_std:
            std_network = MLP(
                input_shape=(obs_dim, ),
                input_layer=mean_network.input_layer,
                output_dim=action_dim,
                hidden_sizes=std_hidden_sizes,
                hidden_nonlinearity=std_hidden_nonlinearity,
                output_nonlinearity=None,
            )
            l_log_std = std_network.output_layer
        else:
            l_log_std = ParamLayer(
                mean_network.input_layer,
                num_units=action_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std",
                trainable=learn_std,
            )

        self.min_std = min_std

        mean_var, log_std_var = L.get_output([l_mean, l_log_std])

        if self.min_std is not None:
            log_std_var = TT.maximum(log_std_var, np.log(min_std))

        self._mean_var, self._log_std_var = mean_var, log_std_var

        self._l_mean = l_mean
        self._l_log_std = l_log_std

        self._dist = DiagonalGaussian(action_dim)

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(GaussianMLPPolicy, self).__init__(env_spec)

        self._f_dist = ext.compile_function(
            inputs=[obs_var],
            outputs=[mean_var, log_std_var],
        )
Пример #7
0
    def __init__(
            self,
            env_spec,
            mean_hidden_nonlinearity=tf.nn.relu,
            mean_hidden_sizes=(32, 32),
            std_hidden_nonlinearity=tf.nn.relu,
            std_hidden_sizes=(32, 32),
            min_std=1e-6,
    ):
        """
        :param env_spec:
        :param mean_hidden_nonlinearity: nonlinearity used for the mean hidden
                                         layers
        :param mean_hidden_sizes: list of hidden_sizes for the fully-connected hidden layers
        :param std_hidden_nonlinearity: nonlinearity used for the std hidden
                                        layers
        :param std_hidden_sizes: list of hidden_sizes for the fully-connected hidden layers
        :param min_std: whether to make sure that the std is at least some
                        threshold value, to avoid numerical issues
        :return:
        """
        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)
        super(GaussianMLPPolicy, self).__init__(env_spec)

        self.env_spec = env_spec
        gpu_options = tf.GPUOptions(per_process_gpu_memory_fraction=0.2)
        self.sess = tf.Session(config=tf.ConfigProto(gpu_options=gpu_options))
        # Create network
        observation_dim = self.env_spec.observation_space.flat_dim
        self.observations_input = tf.placeholder(tf.float32,
                                                 shape=[None, observation_dim])
        action_dim = self.env_spec.action_space.flat_dim
        with tf.variable_scope('mean') as _:
            mlp_mean_output = tf_util.mlp(self.observations_input,
                                          observation_dim,
                                          mean_hidden_sizes,
                                          mean_hidden_nonlinearity)
            mlp_mean_output_size = mean_hidden_sizes[-1]
            self.mean = tf_util.linear(mlp_mean_output,
                                       mlp_mean_output_size,
                                       action_dim)

        with tf.variable_scope('log_std') as _:
            mlp_std_output = tf_util.mlp(self.observations_input,
                                         observation_dim,
                                         std_hidden_sizes,
                                         std_hidden_nonlinearity)
            mlp_std_output_size = std_hidden_sizes[-1]
            self.log_std = tf_util.linear(mlp_std_output,
                                          mlp_std_output_size,
                                          action_dim)
            self.std = tf.maximum(tf.exp(self.log_std), min_std)

        self._dist = DiagonalGaussian(action_dim)

        self.actions_output = tf.placeholder(tf.float32, shape=[None, action_dim])
        z = (self.actions_output - self.mean) / self.std
        self.log_likelihood = (- tf.log(self.std**2)
                               - z**2 * 0.5
                               - tf.log(2*np.pi) * 0.5)
Пример #8
0
    def __init__(
        self,
        env_spec,
        env,
        latent_dim=2,
        latent_name='bernoulli',
        bilinear_integration=False,
        resample=False,
        hidden_sizes=(32, 32),
        learn_std=True,
        init_std=1.0,
        adaptive_std=False,
        std_share_network=False,
        std_hidden_sizes=(32, 32),
        std_hidden_nonlinearity=NL.tanh,
        hidden_nonlinearity=NL.tanh,
        output_nonlinearity=None,
        min_std=1e-4,
        pkl_path=None,
    ):
        """
        :param latent_dim: dimension of the latent variables
        :param latent_name: distribution of the latent variables
        :param bilinear_integration: Boolean indicator of bilinear integration or simple concatenation
        :param resample: Boolean indicator of resampling at every step or only at the start of the rollout (or whenever
        agent is reset, which can happen several times along the rollout with rollout in utils_snn)
        """
        self.latent_dim = latent_dim  ##could I avoid needing this self for the get_action?
        self.latent_name = latent_name
        self.bilinear_integration = bilinear_integration
        self.resample = resample
        self.min_std = min_std
        self.hidden_sizes = hidden_sizes

        self.pre_fix_latent = np.array(
            []
        )  # if this is not empty when using reset() it will use this latent
        self.latent_fix = np.array(
            [])  # this will hold the latents variable sampled in reset()
        self._set_std_to_0 = False

        self.pkl_path = pkl_path

        if self.pkl_path:
            data = joblib.load(os.path.join(config.PROJECT_PATH,
                                            self.pkl_path))
            self.old_policy = data["policy"]
            self.latent_dim = self.old_policy.latent_dim
            self.latent_name = self.old_policy.latent_name
            self.bilinear_integration = self.old_policy.bilinear_integration
            self.resample = self.old_policy.resample  # this could not be needed...
            self.min_std = self.old_policy.min_std
            self.hidden_sizes_snn = self.old_policy.hidden_sizes

        if latent_name == 'normal':
            self.latent_dist = DiagonalGaussian(self.latent_dim)
            self.latent_dist_info = dict(mean=np.zeros(self.latent_dim),
                                         log_std=np.zeros(self.latent_dim))
        elif latent_name == 'bernoulli':
            self.latent_dist = Bernoulli(self.latent_dim)
            self.latent_dist_info = dict(p=0.5 * np.ones(self.latent_dim))
        elif latent_name == 'categorical':
            self.latent_dist = Categorical(self.latent_dim)
            if self.latent_dim > 0:
                self.latent_dist_info = dict(prob=1. / self.latent_dim *
                                             np.ones(self.latent_dim))
            else:
                self.latent_dist_info = dict(prob=np.ones(self.latent_dim))
        else:
            raise NotImplementedError

        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        # retrieve dimensions from env!
        if isinstance(env, MazeEnv) or isinstance(env, GatherEnv):
            self.obs_robot_dim = env.robot_observation_space.flat_dim
            self.obs_maze_dim = env.maze_observation_space.flat_dim
        elif isinstance(env, NormalizedEnv):
            if isinstance(env.wrapped_env, MazeEnv) or isinstance(
                    env.wrapped_env, GatherEnv):
                self.obs_robot_dim = env.wrapped_env.robot_observation_space.flat_dim
                self.obs_maze_dim = env.wrapped_env.maze_observation_space.flat_dim
            else:
                self.obs_robot_dim = env.wrapped_env.observation_space.flat_dim
                self.obs_maze_dim = 0
        else:
            self.obs_robot_dim = env.observation_space.flat_dim
            self.obs_maze_dim = 0
        # print("the dims of the env are(rob/maze): ", self.obs_robot_dim, self.obs_maze_dim)
        all_obs_dim = env_spec.observation_space.flat_dim
        assert all_obs_dim == self.obs_robot_dim + self.obs_maze_dim

        if self.bilinear_integration:
            obs_dim = self.obs_robot_dim + self.latent_dim +\
                      self.obs_robot_dim * self.latent_dim
        else:
            obs_dim = self.obs_robot_dim + self.latent_dim  # here only if concat.

        action_dim = env_spec.action_space.flat_dim

        # for _ in range(10):
        #     print("OK!")
        # print(obs_dim)
        # print(env_spec.observation_space.flat_dim)
        # print(self.latent_dim)

        mean_network = MLP(
            input_shape=(obs_dim, ),
            output_dim=action_dim,
            hidden_sizes=hidden_sizes,
            hidden_nonlinearity=hidden_nonlinearity,
            output_nonlinearity=output_nonlinearity,
            name="meanMLP",
        )

        self._layers_mean = mean_network.layers
        l_mean = mean_network.output_layer
        obs_var = mean_network.input_layer.input_var

        if adaptive_std:
            log_std_network = MLP(input_shape=(obs_dim, ),
                                  input_var=obs_var,
                                  output_dim=action_dim,
                                  hidden_sizes=std_hidden_sizes,
                                  hidden_nonlinearity=std_hidden_nonlinearity,
                                  output_nonlinearity=None,
                                  name="log_stdMLP")
            l_log_std = log_std_network.output_layer
            self._layers_log_std = log_std_network.layers
        else:
            l_log_std = ParamLayer(
                mean_network.input_layer,
                num_units=action_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std",
                trainable=learn_std,
            )
            self._layers_log_std = [l_log_std]

        self._layers_snn = self._layers_mean + self._layers_log_std  # this returns a list with the "snn" layers

        if self.pkl_path:  # restore from pkl file
            data = joblib.load(os.path.join(config.PROJECT_PATH,
                                            self.pkl_path))
            warm_params = data['policy'].get_params_internal()
            self.set_params_snn(warm_params)

        mean_var, log_std_var = L.get_output([l_mean, l_log_std])

        if self.min_std is not None:
            log_std_var = TT.maximum(log_std_var, np.log(self.min_std))

        self._l_mean = l_mean
        self._l_log_std = l_log_std

        self._dist = DiagonalGaussian(action_dim)

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(GaussianMLPPolicy_snn_restorable, self).__init__(env_spec)

        self._f_dist = ext.compile_function(
            inputs=[obs_var],
            outputs=[mean_var, log_std_var],
        )
    def __init__(
            self,
            env_spec,
            env,
            pkl_path=None,
            json_path=None,
            npz_path=None,
            trainable_snn=True,
            ##CF - latents units at the input
            latent_dim=3,  # we keep all these as the dim of the output of the other MLP and others that we will need!
            latent_name='categorical',
            bilinear_integration=False,  # again, needs to match!
            resample=False,  # this can change: frequency of resampling the latent?
            hidden_sizes_snn=(32, 32),
            hidden_sizes_selector=(10, 10),
            external_latent=False,
            learn_std=True,
            init_std=1.0,
            adaptive_std=False,
            std_share_network=False,
            std_hidden_sizes=(32, 32),
            std_hidden_nonlinearity=NL.tanh,
            hidden_nonlinearity=NL.tanh,
            output_nonlinearity=None,
            min_std=1e-4,
    ):
        self.latent_dim = latent_dim  ## could I avoid needing this self for the get_action?
        self.latent_name = latent_name
        self.bilinear_integration = bilinear_integration
        self.resample = resample
        self.min_std = min_std
        self.hidden_sizes_snn = hidden_sizes_snn
        self.hidden_sizes_selector = hidden_sizes_selector

        self.pre_fix_latent = np.array([])  # if this is not empty when using reset() it will use this latent
        self.latent_fix = np.array([])  # this will hold the latents variable sampled in reset()
        self.shared_latent_var = theano.shared(self.latent_fix)  # this is for external lat! update that
        self._set_std_to_0 = False

        self.trainable_snn = trainable_snn
        self.external_latent = external_latent
        self.pkl_path = pkl_path
        self.json_path = json_path
        self.npz_path = npz_path
        self.old_policy = None

        if self.json_path:  # there is another one after defining all the NN to warm-start the params of the SNN
            data = json.load(
                open(os.path.join(config.PROJECT_PATH, self.json_path), 'r'))  # I should do this with the json file
            self.old_policy_json = data['json_args']["policy"]
            self.latent_dim = self.old_policy_json['latent_dim']
            self.latent_name = self.old_policy_json['latent_name']
            self.bilinear_integration = self.old_policy_json['bilinear_integration']
            self.resample = self.old_policy_json['resample']  # this could not be needed...
            self.min_std = self.old_policy_json['min_std']
            self.hidden_sizes_snn = self.old_policy_json['hidden_sizes']
        elif self.pkl_path:
            data = joblib.load(os.path.join(config.PROJECT_PATH, self.pkl_path))
            self.old_policy = data["policy"]
            self.latent_dim = self.old_policy.latent_dim
            self.latent_name = self.old_policy.latent_name
            self.bilinear_integration = self.old_policy.bilinear_integration
            self.resample = self.old_policy.resample  # this could not be needed...
            self.min_std = self.old_policy.min_std
            self.hidden_sizes_snn = self.old_policy.hidden_sizes

        if self.latent_name == 'normal':
            self.latent_dist = DiagonalGaussian(self.latent_dim)
            self.latent_dist_info = dict(mean=np.zeros(self.latent_dim), log_std=np.zeros(self.latent_dim))
        elif self.latent_name == 'bernoulli':
            self.latent_dist = Bernoulli(self.latent_dim)
            self.latent_dist_info = dict(p=0.5 * np.ones(self.latent_dim))
        elif self.latent_name == 'categorical':
            self.latent_dist = Categorical(self.latent_dim)
            if self.latent_dim > 0:
                self.latent_dist_info = dict(prob=1. / self.latent_dim * np.ones(self.latent_dim))
            else:
                self.latent_dist_info = dict(prob=np.ones(self.latent_dim))  # this is an empty array
        else:
            raise NotImplementedError

        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        # retrieve dimensions and check consistency
        if isinstance(env, MazeEnv) or isinstance(env, GatherEnv):
            self.obs_robot_dim = env.robot_observation_space.flat_dim
            self.obs_maze_dim = env.maze_observation_space.flat_dim
        elif isinstance(env, NormalizedEnv):
            if isinstance(env.wrapped_env, MazeEnv) or isinstance(env.wrapped_env, GatherEnv):
                self.obs_robot_dim = env.wrapped_env.robot_observation_space.flat_dim
                self.obs_maze_dim = env.wrapped_env.maze_observation_space.flat_dim
            else:
                self.obs_robot_dim = env.wrapped_env.observation_space.flat_dim
                self.obs_maze_dim = 0
        else:
            self.obs_robot_dim = env.observation_space.flat_dim
            self.obs_maze_dim = 0
        # print("the dims of the env are(rob/maze): ", self.obs_robot_dim, self.obs_maze_dim)
        all_obs_dim = env_spec.observation_space.flat_dim
        assert all_obs_dim == self.obs_robot_dim + self.obs_maze_dim

        if self.external_latent:  # in case we want to fix the latent externally
            l_all_obs_var = L.InputLayer(shape=(None,) + (self.obs_robot_dim + self.obs_maze_dim,))
            all_obs_var = l_all_obs_var.input_var
            # l_selection = ConstOutputLayer(incoming=l_all_obs_var, output_var=self.shared_latent_var)
            l_selection = ParamLayer(incoming=l_all_obs_var, num_units=self.latent_dim, param=self.shared_latent_var,
                                     trainable=False) # Rui: change False to True? this is a simple layer that directly outputs self.shared_latent_var
            selection_var = L.get_output(l_selection)

        else:
            # create network with softmax output: it will be the latent 'selector'!
            latent_selection_network = MLP(
                input_shape=(self.obs_robot_dim + self.obs_maze_dim,),
                output_dim=self.latent_dim,
                hidden_sizes=self.hidden_sizes_selector,
                hidden_nonlinearity=hidden_nonlinearity,
                output_nonlinearity=NL.softmax,
            )
            l_all_obs_var = latent_selection_network.input_layer
            all_obs_var = latent_selection_network.input_layer.input_var

            # collect the output to select the behavior of the robot controller (equivalent to latents)
            l_selection = latent_selection_network.output_layer
            selection_var = L.get_output(l_selection)

        # split all_obs into the robot and the maze obs --> ROBOT goes first!!
        l_obs_robot = CropLayer(l_all_obs_var, start_index=None, end_index=self.obs_robot_dim)
        l_obs_maze = CropLayer(l_all_obs_var, start_index=self.obs_robot_dim, end_index=None)
        # for _ in range(10):
        #     print("OK!")
        # print(self.obs_robot_dim)
        # print(self.obs_maze_dim)

        obs_robot_var = all_obs_var[:, :self.obs_robot_dim]
        obs_maze_var = all_obs_var[:, self.obs_robot_dim:]

        # Enlarge obs with the selectors (or latents). Here just computing the final input dim
        if self.bilinear_integration:
            l_obs_snn = BilinearIntegrationLayer([l_obs_robot, l_selection])
        else:
            l_obs_snn = L.ConcatLayer([l_obs_robot, l_selection])

        action_dim = env_spec.action_space.flat_dim

        # create the action network
        mean_network = MLP(
            input_layer=l_obs_snn,  # input the layer that handles the integration of the selector
            output_dim=action_dim,
            hidden_sizes=self.hidden_sizes_snn,
            hidden_nonlinearity=hidden_nonlinearity,
            output_nonlinearity=output_nonlinearity,
            name="meanMLP",
        )

        self._layers_mean = mean_network.layers
        l_mean = mean_network.output_layer

        if adaptive_std:
            log_std_network = MLP(
                input_layer=l_obs_snn,
                output_dim=action_dim,
                hidden_sizes=std_hidden_sizes,
                hidden_nonlinearity=std_hidden_nonlinearity,
                output_nonlinearity=None,
                name="log_stdMLP"
            )
            l_log_std = log_std_network.output_layer
            self._layers_log_std = log_std_network.layers
        else:
            l_log_std = ParamLayer(
                incoming=mean_network.input_layer,
                num_units=action_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std",
                trainable=learn_std,
            )
            self._layers_log_std = [l_log_std]

        self._layers_snn = self._layers_mean + self._layers_log_std  # this returns a list with the "snn" layers

        if not self.trainable_snn:
            for layer in self._layers_snn:
                for param, tags in layer.params.items():  # params of layer are OrDict: key=the shared var, val=tags
                    tags.remove("trainable")

        if self.json_path and self.npz_path:
            warm_params_dict = dict(np.load(os.path.join(config.PROJECT_PATH, self.npz_path)))
            # keys = list(param_dict.keys())
            self.set_params_snn(warm_params_dict)
        elif self.pkl_path:
            data = joblib.load(os.path.join(config.PROJECT_PATH, self.pkl_path))
            warm_params = data['policy'].get_params_internal()
            self.set_params_snn(warm_params)

        mean_var, log_std_var = L.get_output([l_mean, l_log_std])

        if self.min_std is not None:
            log_std_var = TT.maximum(log_std_var, np.log(self.min_std))

        self._l_mean = l_mean
        self._l_log_std = l_log_std

        self._dist = DiagonalGaussian(action_dim)

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(GaussianMLPPolicy_snn_hier, self).__init__(env_spec)

        # debug
        obs_snn_var = L.get_output(l_obs_snn)
        self._l_obs_snn = ext.compile_function(
            inputs=[all_obs_var],
            outputs=obs_snn_var,
        )
        # self._log_std = ext.compile_function(
        #     inputs=[all_obs_var],
        #     outputs=log_std_var,
        # )
        self._mean = ext.compile_function(
            inputs=[all_obs_var],
            outputs=mean_var,
        )

        self._f_dist = ext.compile_function(
            inputs=[all_obs_var],
            outputs=[mean_var, log_std_var],
        )
        # if I want to monitor the selector output
        self._f_select = ext.compile_function(
            inputs=[all_obs_var],
            outputs=selection_var,
        )
    def __init__(
        self,
        env_spec,
        env,
        pkl_paths=(),
        json_paths=(),
        npz_paths=(),
        trainable_old=True,
        external_selector=False,
        hidden_sizes_selector=(10, 10),
        learn_std=True,
        init_std=1.0,
        adaptive_std=False,
        std_share_network=False,
        std_hidden_sizes=(32, 32),
        std_hidden_nonlinearity=NL.tanh,
        hidden_nonlinearity=NL.tanh,
        output_nonlinearity=None,
        min_std=1e-4,
    ):
        """
        :param pkl_paths: tuple/list of pkl paths
        :param json_paths: tuple/list of json paths
        :param npz_paths: tuple/list of npz paths
        :param trainable_old: Are the old policies still trainable
        :param external_selector: is the linear combination of the old policies outputs fixed externally
        :param hidden_sizes: list of sizes for the fully-connected hidden layers
        :param learn_std: Is std trainable
        :param init_std: Initial std
        :param adaptive_std:
        :param std_share_network:
        :param std_hidden_sizes: list of sizes for the fully-connected layers for std
        :param min_std: whether to make sure that the std is at least some threshold value, to avoid numerical issues
        :param std_hidden_nonlinearity:
        :param hidden_nonlinearity: nonlinearity used for each hidden layer
        :param output_nonlinearity: nonlinearity for the output layer
        :param mean_network: custom network for the output mean
        :param std_network: custom network for the output log std
        """
        # define where are the old policies to use and what to do with them:
        self.trainable_old = trainable_old  # whether to keep training the old policies loaded here
        self.pkl_paths = pkl_paths
        self.json_paths = json_paths
        self.npz_paths = npz_paths
        self.selector_dim = max(
            len(json_paths), len(pkl_paths))  # pkl could be zero if giving npz
        # if not use a selector NN here, just externally fixed selector variable:
        self.external_selector = external_selector  # whether to use the selectorNN defined here or the pre_fix_selector
        self.pre_fix_selector = np.zeros(
            (self.selector_dim)
        )  # if this is not empty when using reset() it will use this selector
        self.selector_fix = np.zeros(
            (self.selector_dim
             ))  # this will hold the selectors variable sampled in reset()
        self.shared_selector_var = theano.shared(
            self.selector_fix)  # this is for external selector! update that
        # else, describe the MLP used:
        self.hidden_sizes_selector = hidden_sizes_selector  # size of the selector NN defined here
        self.min_std = min_std
        self._set_std_to_0 = False

        self.action_dim = env_spec.action_space.flat_dim  # not checking that all the old policies have this act_dim

        self.old_hidden_sizes = []
        # assume json always given
        for json_path in self.json_paths:
            data = json.load(
                open(os.path.join(config.PROJECT_PATH, json_path), 'r'))
            old_json_policy = data['json_args']["policy"]
            self.old_hidden_sizes.append(old_json_policy['hidden_sizes'])

        # retrieve dimensions and check consistency
        if isinstance(env, MazeEnv) or isinstance(env, GatherEnv):
            self.obs_robot_dim = env.robot_observation_space.flat_dim
            self.obs_maze_dim = env.maze_observation_space.flat_dim
        elif isinstance(env, NormalizedEnv):
            if isinstance(env.wrapped_env, MazeEnv) or isinstance(
                    env.wrapped_env, GatherEnv):
                self.obs_robot_dim = env.wrapped_env.robot_observation_space.flat_dim
                self.obs_maze_dim = env.wrapped_env.maze_observation_space.flat_dim
            else:
                self.obs_robot_dim = env.wrapped_env.observation_space.flat_dim
                self.obs_maze_dim = 0
        else:
            self.obs_robot_dim = env.observation_space.flat_dim
            self.obs_maze_dim = 0
        # print("the dims of the env are(rob/maze): ", self.obs_robot_dim, self.obs_maze_dim)
        all_obs_dim = env_spec.observation_space.flat_dim
        assert all_obs_dim == self.obs_robot_dim + self.obs_maze_dim
        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        if self.external_selector:  # in case we want to fix the selector externally
            l_all_obs_var = L.InputLayer(
                shape=(None, ) + (self.obs_robot_dim + self.obs_maze_dim, ))
            all_obs_var = l_all_obs_var.input_var
            l_selection = ParamLayer(incoming=l_all_obs_var,
                                     num_units=self.selector_dim,
                                     param=self.shared_selector_var,
                                     trainable=False)
            selection_var = L.get_output(l_selection)
        else:
            # create network with softmax output: it will be the selector!
            selector_network = MLP(
                input_shape=(self.obs_robot_dim + self.obs_maze_dim, ),
                output_dim=self.selector_dim,
                hidden_sizes=self.hidden_sizes_selector,
                hidden_nonlinearity=hidden_nonlinearity,
                output_nonlinearity=NL.softmax,
            )
            l_all_obs_var = selector_network.input_layer
            all_obs_var = selector_network.input_layer.input_var

            # collect the output to select the behavior of the robot controller (equivalent to selectors)
            l_selection = selector_network.output_layer
            selection_var = L.get_output(l_selection)

        # split all_obs into the robot and the maze obs --> ROBOT goes first!!
        l_obs_robot = CropLayer(l_all_obs_var,
                                start_index=None,
                                end_index=self.obs_robot_dim)
        l_obs_maze = CropLayer(l_all_obs_var,
                               start_index=self.obs_robot_dim,
                               end_index=None)

        obs_robot_var = all_obs_var[:, :self.obs_robot_dim]
        obs_maze_var = all_obs_var[:, self.obs_robot_dim:]

        # create the action networks
        self.old_l_means = [
        ]  # I do this self in case I wanna access it from reset
        self.old_l_log_stds = []
        self.old_layers = []
        for i in range(self.selector_dim):
            mean_network = MLP(
                input_layer=l_obs_robot,
                output_dim=self.action_dim,
                hidden_sizes=self.old_hidden_sizes[i],
                hidden_nonlinearity=hidden_nonlinearity,
                output_nonlinearity=output_nonlinearity,
                name="meanMLP{}".format(i),
            )
            self.old_l_means.append(mean_network.output_layer)
            self.old_layers += mean_network.layers

            l_log_std = ParamLayer(
                incoming=mean_network.input_layer,
                num_units=self.action_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std{}".format(i),
                trainable=learn_std,
            )
            self.old_l_log_stds.append(l_log_std)
            self.old_layers += [l_log_std]

        if not self.trainable_old:
            for layer in self.old_layers:
                for param, tags in layer.params.items(
                ):  # params of layer are OrDict: key=the shared var, val=tags
                    tags.remove("trainable")

        if self.json_paths and self.npz_paths:
            old_params_dict = {}
            for i, npz_path in enumerate(self.npz_paths):
                params_dict = dict(
                    np.load(os.path.join(config.PROJECT_PATH, npz_path)))
                renamed_warm_params_dict = {}
                for key in params_dict.keys():
                    if key == 'output_log_std.param':
                        old_params_dict['output_log_std{}.param'.format(
                            i)] = params_dict[key]
                    elif 'meanMLP_' == key[:8]:
                        old_params_dict['meanMLP{}_'.format(i) +
                                        key[8:]] = params_dict[key]
                    else:
                        old_params_dict['meanMLP{}_'.format(i) +
                                        key] = params_dict[key]
            self.set_old_params(old_params_dict)

        elif self.pkl_paths:
            old_params_dict = {}
            for i, pkl_path in enumerate(self.pkl_paths):
                data = joblib.load(os.path.join(config.PROJECT_PATH, pkl_path))
                params = data['policy'].get_params_internal()
                for param in params:
                    if param.name == 'output_log_std.param':
                        old_params_dict['output_log_std{}.param'.format(
                            i)] = param.get_value()
                    elif 'meanMLP_' == param.name[:8]:
                        old_params_dict['meanMLP{}_'.format(i) +
                                        param.name[8:]] = param.get_value()
                    else:
                        old_params_dict['meanMLP{}_'.format(i) +
                                        param.name] = param.get_value()
            self.set_old_params(old_params_dict)

        # new layers actually selecting the correct output
        l_mean = SumProdLayer(self.old_l_means + [l_selection])
        l_log_std = SumProdLayer(self.old_l_log_stds + [l_selection])
        mean_var, log_std_var = L.get_output([l_mean, l_log_std])

        if self.min_std is not None:
            log_std_var = TT.maximum(log_std_var, np.log(self.min_std))

        self._l_mean = l_mean
        self._l_log_std = l_log_std

        self._dist = DiagonalGaussian(self.action_dim)

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(GaussianMLPPolicy_multi_hier, self).__init__(env_spec)

        self._f_old_means = ext.compile_function(
            inputs=[all_obs_var],
            outputs=[
                L.get_output(l_old_mean) for l_old_mean in self.old_l_means
            ])

        self._f_all_inputs = ext.compile_function(
            inputs=[all_obs_var],
            outputs=[
                L.get_output(l_old_mean) for l_old_mean in self.old_l_means
            ] + [selection_var])

        self._f_dist = ext.compile_function(
            inputs=[all_obs_var],
            outputs=[mean_var, log_std_var],
        )
        # if I want to monitor the selector output
        self._f_select = ext.compile_function(
            inputs=[all_obs_var],
            outputs=selection_var,
        )
Пример #11
0
    def __init__(
        self,
        env_spec,
        latent_dim=2,
        latent_name='bernoulli',
        bilinear_integration=False,
        resample=False,
        hidden_sizes=(32, 32),
        learn_std=True,
        init_std=1.0,
        adaptive_std=False,
        std_share_network=False,
        std_hidden_sizes=(32, 32),
        std_hidden_nonlinearity=NL.tanh,
        hidden_nonlinearity=NL.tanh,
        output_nonlinearity=None,
        min_std=1e-4,
    ):
        """
        :param latent_dim: dimension of the latent variables
        :param latent_name: distribution of the latent variables
        :param bilinear_integration: Boolean indicator of bilinear integration or simple concatenation
        :param resample: Boolean indicator of resampling at every step or only at the start of the rollout (or whenever
        agent is reset, which can happen several times along the rollout with rollout in utils_snn)
        """
        self.latent_dim = latent_dim  ##could I avoid needing this self for the get_action?
        self.latent_name = latent_name
        self.bilinear_integration = bilinear_integration
        self.resample = resample
        self.min_std = min_std
        self.hidden_sizes = hidden_sizes

        self.pre_fix_latent = np.array(
            []
        )  # if this is not empty when using reset() it will use this latent
        self.latent_fix = np.array(
            [])  # this will hold the latents variable sampled in reset()
        self._set_std_to_0 = False

        if latent_name == 'normal':
            self.latent_dist = DiagonalGaussian(self.latent_dim)
            self.latent_dist_info = dict(mean=np.zeros(self.latent_dim),
                                         log_std=np.zeros(self.latent_dim))
        elif latent_name == 'bernoulli':
            self.latent_dist = Bernoulli(self.latent_dim)
            self.latent_dist_info = dict(p=0.5 * np.ones(self.latent_dim))
        elif latent_name == 'categorical':
            self.latent_dist = Categorical(self.latent_dim)
            if self.latent_dim > 0:
                self.latent_dist_info = dict(prob=1. / self.latent_dim *
                                             np.ones(self.latent_dim))
            else:
                self.latent_dist_info = dict(prob=np.ones(self.latent_dim))
        else:
            raise NotImplementedError

        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        if self.bilinear_integration:
            obs_dim = env_spec.observation_space.flat_dim + latent_dim +\
                      env_spec.observation_space.flat_dim * latent_dim
        else:
            obs_dim = env_spec.observation_space.flat_dim + latent_dim  # here only if concat.

        action_dim = env_spec.action_space.flat_dim

        mean_network = MLP(
            input_shape=(obs_dim, ),
            output_dim=action_dim,
            hidden_sizes=hidden_sizes,
            hidden_nonlinearity=hidden_nonlinearity,
            output_nonlinearity=output_nonlinearity,
            name="meanMLP",
        )

        l_mean = mean_network.output_layer
        obs_var = mean_network.input_layer.input_var

        if adaptive_std:
            l_log_std = MLP(input_shape=(obs_dim, ),
                            input_var=obs_var,
                            output_dim=action_dim,
                            hidden_sizes=std_hidden_sizes,
                            hidden_nonlinearity=std_hidden_nonlinearity,
                            output_nonlinearity=None,
                            name="log_stdMLP").output_layer
        else:
            l_log_std = ParamLayer(
                mean_network.input_layer,
                num_units=action_dim,
                param=lasagne.init.Constant(np.log(init_std)),
                name="output_log_std",
                trainable=learn_std,
            )

        mean_var, log_std_var = L.get_output([l_mean, l_log_std])

        if self.min_std is not None:
            log_std_var = TT.maximum(log_std_var, np.log(self.min_std))

        self._l_mean = l_mean
        self._l_log_std = l_log_std

        self._dist = DiagonalGaussian(action_dim)

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(GaussianMLPPolicy_snn, self).__init__(env_spec)

        self._f_dist = ext.compile_function(
            inputs=[obs_var],
            outputs=[mean_var, log_std_var],
        )
Пример #12
0
    def __init__(
        self,
        env_spec,
        input_latent_vars=None,
        hidden_sizes=(32, 32),
        hidden_latent_vars=None,
        learn_std=True,
        init_std=1.0,
        hidden_nonlinearity=NL.tanh,
        output_nonlinearity=None,
    ):
        Serializable.quick_init(self, locals())
        assert isinstance(env_spec.action_space, Box)

        obs_dim = env_spec.observation_space.flat_dim
        action_dim = env_spec.action_space.flat_dim

        # create network
        mean_network = StochasticMLP(
            input_shape=(obs_dim, ),
            input_latent_vars=input_latent_vars,
            output_dim=action_dim,
            hidden_sizes=hidden_sizes,
            hidden_latent_vars=hidden_latent_vars,
            hidden_nonlinearity=hidden_nonlinearity,
            output_nonlinearity=output_nonlinearity,
        )

        l_mean = mean_network.output_layer
        obs_var = mean_network.input_layer.input_var

        l_log_std = ParamLayer(
            mean_network.input_layer,
            num_units=action_dim,
            param=lasagne.init.Constant(np.log(init_std)),
            name="output_log_std",
            trainable=learn_std,
        )

        self._mean_network = mean_network
        self._n_latent_layers = len(mean_network.latent_layers)
        self._l_mean = l_mean
        self._l_log_std = l_log_std

        LasagnePowered.__init__(self, [l_mean, l_log_std])
        super(StochasticGaussianMLPPolicy, self).__init__(env_spec)

        outputs = self.dist_info_sym(mean_network.input_var)
        latent_keys = sorted(
            set(outputs.keys()).difference({"mean", "log_std"}))

        extras = get_full_output([self._l_mean, self._l_log_std] +
                                 self._mean_network.latent_layers, )[1]
        latent_distributions = [
            extras[layer]["distribution"]
            for layer in self._mean_network.latent_layers
        ]

        self._latent_keys = latent_keys
        self._latent_distributions = latent_distributions
        self._dist = DiagonalGaussian(action_dim)

        self._f_dist_info = ext.compile_function(
            inputs=[obs_var],
            outputs=outputs,
        )
        self._f_dist_info_givens = None