Dear Barna,

sorry, this somehow slipped our attention for way too long.

Can you please check if the code in solves the problem for you?


On 19.02.22 01:32, Barna Zajzon wrote:

Dear all,

I'm encountering the following error

    python: /home/zbarni/software/packages/nest/znest/nestkernel/model_manager.h:296: nest::Model* nest::ModelManager::get_node_model(nest::index) const: Assertion `m < node_models_.size()' failed.

when using the following code:

nest.SetKernelStatus({'total_num_virtual_procs': 16, 'local_num_threads': 16})

for i in range(16):
    nest.CopyModel('MyNeuron', f'MyNeuron_{i}')

neurons = nest.Create('MyNeuron_0', 2)
nest.Connect(neurons, neurons)

The script uses a neuron model that I wrote in C++ and is loaded without errors. The error is thrown upon nest.Connect(), and goes away if I create the neurons using `MyNeuron` and not `MyNeuron_x` (copied) or if the #vp and #threads is 1. I've used the model with NEST 2.20.0 without problems, but I'd like to port the code to the latest version. Maybe I'm just missing something new functionality/API related to CopyModel and multiprocessing - have there been any critical changes in the model requirements?

Any help would be greatly appreciated.


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