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Wrappers
############

*Sinergym* has several **wrappers** in order to add some functionality in the environment 
that it doesn't have by default. Currently, we have developed a **normalization wrapper**, 
**multi-observation wrapper** and **Logger wrapper**. The code can be found in 
`sinergym/sinergym/utils/wrappers.py <https://github.com/ugr-sail/sinergym/blob/main/sinergym/utils/wrappers.py>`__.
You can implement your own wrappers inheriting from *gym.Wrapper* or some of its variants.

An usage of these wrappers could be the next:

.. code:: python

    import gym
    import sinergym
    from sinergym.utils.wrapper import LoggerWrapper, NormalizeObservation

    env = gym.make('Eplus-5Zone-hot-continuous-v1')
    env = NormalizeObservation(env)
    env = LoggerWrapper(env)
    ...

    for i in range(1):
        obs = env.reset()
        rewards = []
        done = False
        current_month = 0
        while not done:
            a = env.action_space.sample()
            obs, reward, done, info = env.step(a)
            rewards.append(reward)
            if info['month'] != current_month:  # display results every month
                current_month = info['month']
                print('Reward: ', sum(rewards), info)
        print(
            'Episode ',
            i,
            'Mean reward: ',
            np.mean(rewards),
            'Cumulative reward: ',
            sum(rewards))
    env.close()

.. warning:: The order of wrappers if you are going to use several at the same time is really important.
             The correct order is **Normalization - Logger - MultiObs** and subsets (for example, *Normalization* - *Multiobs* is valid).

.. warning:: If you add new observation variables to the environment than the default ones, you have 
             to update the **value range dictionary** in `sinergym/sinergym/utils/constants.py <https://github.com/ugr-sail/sinergym/blob/main/sinergym/utils/constants.py>`__ 
             so that normalization can be applied correctly. Otherwise, you will encounter bug `#249 <https://github.com/ugr-sail/sinergym/issues/249>`__.

.. note:: For more information about *Sinergym* Logger, visit :ref:`Logger`.