Simple FACMAC Observations only include last Other Agents velocity?

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Good morning

In running the Simple FACMAC environment it appears observations comprise :

• own velocity: x, y
• own position: x,y
• landmark positions: x,y for each (if any)
• other agent relative positions: x,y for each
• other agent velocities: x,y

Currently it appears the other agent velocities only include the final other agent due to the slice [-1:] in 'simple_facmac.py':

def _good(aidx):
    return jnp.concatenate(
        [
            state.p_vel[aidx].flatten(),  # 2
            state.p_pos[aidx].flatten(),  # 2
            landmark_pos[aidx].flatten(),  # 5, 2
            other_pos[aidx].flatten(),  # 5, 2
            jnp.zeros_like(other_vel[aidx, -1:].flatten())  # SLICE IS HERE
        ]
    )

def _adversary(aidx):
    return jnp.concatenate(
        [
            state.p_vel[aidx].flatten(),  # 2
            state.p_pos[aidx].flatten(),  # 2
            landmark_pos[aidx].flatten(),  # 5, 2
            other_pos[aidx].flatten(),  # 5, 2
            other_vel[aidx, -1:].flatten(),  # SLICE IS HERE
        ]
    )

Have I interpreted this correctly? Or should all the other agent velocities be included in the observation to pair-up with their positions (which appears so I think in the original FACMAC paper code)?

thank you