# Action space compatibility with algorithms

**URL:** <https://discuss.ray.io/t/action-space-compatibility-with-algorithms/10632>\
**Category:** RLlib\
**Created:** [May 12, 2023, 8:08am UTC](https://discuss.ray.io/t/action-space-compatibility-with-algorithms/10632 "2023-05-12T08:08:41Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Douae\_Ahmadoun](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/douae_ahmadoun/32/4070_2.png) [@Douae\_Ahmadoun](https://discuss.ray.io/u/Douae_Ahmadoun)\
**Post date:** [May 12, 2023, 8:08am UTC](https://discuss.ray.io/t/action-space-compatibility-with-algorithms/10632/1 "2023-05-12T08:08:41Z")

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Hello community,

I had this exception with DQN and DDPG but not with PPO.

```auto
UnsupportedSpaceException: Action space (Dict('agent_1': Discrete(5), 'agent_2': Discrete(5))) of DDPGTorchPolicy is not supported for DDPG.

```

Do we have somewhere in the documentation (or elsewhere) more information on which action spaces are supported or not by which algorithms?

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<div class="post-metadata">

**Author:** ![Rohan138](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/rohan138/32/1160_2.png) [@Rohan138](https://discuss.ray.io/u/Rohan138)\
**Post date:** [May 23, 2023, 12:31am UTC](https://discuss.ray.io/t/action-space-compatibility-with-algorithms/10632/2 "2023-05-23T00:31:19Z")

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Here’s the doc on discrete/continuous action support: [Algorithms — Ray 2.4.0](https://docs.ray.io/en/latest/rllib/rllib-algorithms.html)

DDPG does not support Discrete action spaces, so it cannot support Dict[…, Discrete]. MADDPG: [Algorithms — Ray 2.4.0](https://docs.ray.io/en/latest/rllib/rllib-algorithms.html#maddpg) may be what you’re looking for?

DQN should support it though; could you post your full algorithm config and multi-agent policy\_mapping\_fn?