Should NEST Device Ids be relative to avoid confusion

[drodarie]

The ids of the targets stored in the NEO files corresponds to the global NEST ids which are useless for the user as they don't know in which order the targets were loaded in NEST, especially since targets can be cells or connections.

I would store local/relative ids instead, since the user can recover the targeted scaffold objects in the same order after the simulation but cannot get the NEST ids. Example with the SpikeRecorder:

    def implement(self, adapter, simulation, simdata):
        nodes = self.get_target_nodes(adapter, simulation, simdata)
        device = self.register_device(simdata, nest.Create("spike_recorder"))
        self.connect_to_nodes(device, nodes)

        def recorder(segment):
              segment.spiketrains.append(
                              SpikeTrain(
                                  device.events["times"],
                                  units="ms",
                                  # Add the commented code to subtract the first id of the NEST Nodecollection 
                                  array_annotations={"senders": device.events["senders"]},  # - nodes.tolist()[0]
                                  t_stop=simulation.duration,
                                  device=self.name,
                                  pop_size=len(nodes),
                              )
                          )

[drodarie]

NEST does not allow you to create a connection on a connection, meaning you cannot nest.Connect on a synapse.
So we should prevent the user to target synapses when using devices.

Note that the only exception are weight_recorder but you have to declare it when you create the synapse.
https://nest-simulator.readthedocs.io/en/v3.9/models/weight_recorder.html