<p>I found that we shouldn't eliminate those actions, because <code>RIGHTFIRE</code> and <code>LEFTFIRE</code> do <code>RIGHT</code> + <code>FIRE</code> and <code>LEFT</code> + <code>FIRE</code>, respectively. So they are different actions. I post this just to clarify in case someone faces the same doubt.</p>

CC BY-SA 4.0
2019-03-23T15:04:42.993Z
2020-12-27T13:57:19.517Z
2020-12-27T13:57:19.517Z
JCP
<p>I'm trying to replicate the DeepMind DQN paper. I'm using OpenAI's Gym. I'm trying to get a decent score with Space Invaders (using <code>SpaceInvaders-v4</code> environment). I checked the actions available with <code>env.unwrapped.get_action_meanings()</code>, and I get this:</p>
<pre><code>['NOOP', 'FIRE', 'RIGHT', 'LEFT', 'RIGHTFIRE', 'LEFTFIRE']
</code></pre>
<p>Checking the number of actions with <code>env.action_space.n</code> gives me a number of 6 actions.</p>
<p>The <code>RIGHTFIRE</code> and <code>LEFTFIRE</code> actions, I suppose, aren't used, given that they <em>seem</em> to do the same as <code>LEFT</code> and <code>RIGHT</code>, am I right?</p>
<p>If so, restricting the action size to the 4 first actions would improve my learning?</p>

<reinforcement-learning><dqn><deep-rl><gym><action-spaces>
Should I ignore the actions RIGHTFIRE and LEFTFIRE in the SpaceInvaders environment?
JCP
# Should I ignore the actions RIGHTFIRE and LEFTFIRE in the SpaceInvaders environment?

(Asked by: username_0 on 2019-03-13)

I'm trying to replicate the DeepMind DQN paper. I'm using OpenAI's Gym. I'm trying to get a decent score with Space Invaders (using SpaceInvaders-v4 environment). I checked the actions available with env.unwrapped.get_action_meanings(), and I get this:
['NOOP', 'FIRE', 'RIGHT', 'LEFT', 'RIGHTFIRE', 'LEFTFIRE']

Checking the number of actions with env.action_space.n gives me a number of 6 actions.
The RIGHTFIRE and LEFTFIRE actions, I suppose, aren't used, given that they seem to do the same as LEFT and RIGHT, am I right?
If so, restricting the action size to the 4 first actions would improve my learning?

**Tags:** reinforcement-learning, dqn, deep-rl, gym, action-spaces


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## 1 answers

### Answer by username_0 on 2019-03-23. Score: 0 | Accepted answer

I found that we shouldn't eliminate those actions, because `RIGHTFIRE` and `LEFTFIRE` do `RIGHT` + `FIRE` and `LEFT` + `FIRE`, respectively. So they are different actions. I post this just to clarify in case someone faces the same doubt.


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