Enhance notebook "2_Action_GridManipulation" to make it clear some actions presented are ambiguous

[rte-france]

Enhance notebook "2_Action_GridManipulation" to make it clear some actions presented are ambiguous

[BDonnot]

Hello,

I think this behaviour, though a bit surprising is perfectly fine. In fact, this action is "Ambiguous" (there is no unique way to understand what the user meant by this action).

In this case, it is ambiguous because you asked to connect a powerline, without specifying on which bus. There are 4 different ways to reconnect a powerline in grid2op:

• connect it to bus 1 on origin and bus 1 on extremity
• connect it to bus 2 on origin and bus 1 on extremity
• connect it to bus 1 on origin and bus 2 on extremity
• connect it to bus 2 on origin and bus 2 on extremity

As it's not clear what you meant by "reconnecting" powerline 3 and 4, then it is not performed on the powergrid. On the real "env.step" this is tagged in the "infos" dictionnary. Il will work on adapting it to the "obs.simulate" too.

Note that this behaviour is explained in the text bellow de description of the action:

NB this action is ambiguous so it cannot be implemented on the powergrid. Indeed, powerlines 3 and 4 are reconnected, but we don't specify on which bus!

The fact that the action is silently not implemented is pretty common in video games. For example, in pacman, when you face a wall and want to go forward, you can't (because you face the wall) but nothing is done: the game doesn't crash, and the walls are not "lava". That's the same behaviour in grid2op. Facing an ambiguous or illegal action is equivalent do doing nothing.

I agree this makes a poor example. I will try to rework this part. I switch your issue to an enhancement on the 2nd getting started.

[jhmenke]

Thanks for the answer!

Then i find the notebook a bit confusing, at least for the change_line_status case (see other issue). The demo action does not specify that i need to define a bus for changing the status:

the_same_act = action_space({"set_line_status": [(3,1), (4,1), (5,-1), (6,-1)],
"change_line_status": [0,1,2]
})
print(the_same_act)

[BDonnot]

Indeed i will make it more explicit. Thanks for the valuable comment.

[BDonnot]

This issue has been fixed in latest version (that i'm testing for integration at the moment).
Thanks again for the feedback.