PigChaseSymbolicStateBuilder returns inconsistent states

[batmanzmc]

Hi,

We found that PigChaseSymbolicStateBuilder sometimes returns wrong state information, either agents (or pig) disappear, or the agents at wrong places after executing a moving action.

For example the below figure. At the second last state, the pig and the two agents are there, but in the last state only Agent 2 appears (Agent 1 and the pig disappear). Is this a bug?

Best,
Mengchen

[mfuntowicz]

Hi zmc245 (@batmanzmc),

Thanks for reporting this.

Some few questions to help us :

• Does this behviour happens on a regular basis or totally randomly ?
• In such case, do you see the Pig and the agents on the Minecraft clients ? Or they disappear also ?
• Are you running a script we provide ? In this case which one ?
• What is your system configuration ?
• Can you plot the thread name/id in addition to the state ?
• Which version of Malmo are you running ?

Thanks in advance for the information, and sorry for the inconvenience.
Morgan

[Haishion]

Hi, Funtowicz Morgan (@mfuntowicz)
I set the number of episodes to play as 200, and print the environment state of each step. However, 15% of the steps return wrong state, which means either of the 2 agents and the pig is at a wrong position (i.e., not in the game playing valid positions). I then add some sleep time between actions, but it's still so. May I know whether this is due to the platform or my agent?

[petrosgk]

This issue happens to me too. I've worked around it by checking if both agents and the pig are present in the returned state before having my agent choose an action, otherwise return a random action.