NEST Client -- A client for the NEST Server

The easiest way to interact with the NEST Server is the NEST Client. It can be used either by directly starting a Python session in a clone of that repository, or by installing it by pip install therein. NEST Simulator itself does not have to be installed in order to use the NEST Client.

Using a dynamic function mapping mechanism, the NEST Client supports the same functions as PyNEST does. However, instead of directly executing calls in NEST, it forwards them together with their arguments to the NEST Server, which in turn executes them. To you as a user, everything looks much like a typical simulation code for NEST Simulator.

Install NEST Client

The client can be installed with this command:

pip install nest-client

Basic usage

To give you an idea of the usage, the following table shows a comparison of a typical simulation once for PyNEST and once using the NEST Client identical except for the import statement:

PyNEST directly

via NEST Client

import nest # Reset the kernel nest.ResetKernel() # Create nodes params = {"rate": 6500} pg = nest.Create("poisson_generator", 1, params) neurons = nest.Create("iaf_psc_alpha", 1000) sr = nest.Create("spike_recorder") # Connect nodes nest.Connect(pg, neurons, syn_spec={"weight": 10}) nest.Connect(neurons[::10], sr) # Simulate nest.Simulate(1000) # Get events print("Number of events:", sr.n_events)

from nest_client import NESTClient nest = NESTClient() # Reset the kernel nest.ResetKernel() # Create nodes params = {"rate": 6500} pg = nest.Create("poisson_generator", 1, params) neurons = nest.Create("iaf_psc_alpha", 1000) sr = nest.Create("spike_recorder") # Connect nodes nest.Connect(pg, neurons, syn_spec={"weight": 10}) nest.Connect(neurons[::10], sr) # Simulate nest.Simulate(1000) # Get events n_events = nest.GetStatus(sr, "n_events") print("Number of events:", n_events)

Run scripts

The NEST Client is able to send complete simulation scripts to the NEST Server using the functions exec_script and from_file. The following listing shows a Python snippet using the NEST Server Client to execute a simple script on the Server using the exec_script function:

from nest_client import NESTClient
nest = NESTClient()

script = "print('Hello world!')"
response = nest.exec_script(script)
print(response['stdout'])          # 'Hello world!'

script = "models=nest.node_models"
response = nest.exec_script(script, return_vars='models')
models = response['data']
print(models)                      # the list of models

In a more realistic scenario, you probably already have your simulation script stored in a file. Such scripts can be sent to the NEST Server for execution using the from_file function provided by the NEST Client.

from nest_client import NESTClient

nest = NESTClient()

response = nest.from_file("simulation_script.py", return_vars="n_events")
n_events = response["data"]

print("Number of events:", n_events)

Note

By default, the NEST Server only imports the PyNEST module during startup for security reasons. In case you require additional Python modules for your simulation script, please see NEST Server.

NEST Client API

Call	Description
NESTClient	The client object to interact with the NEST Server
NESTClient.<call>(*args, **kwargs)	Execute a PyNEST function <call> on the NEST Server; the arguments args and kwargs will be forwarded to the function
NESTClient.exec_script(source, return_vars=None)	Execute a Python script on the NEST Server; the script has to be given as a string in the source argument
NESTClient.from_file(filename, return_vars=None)	Execute a Python script on the NEST Server; the argument filename is the name of the file in which the script is stored

Development mode

We recommend to use virtual environment, e.g. with uv:

Install nest-client as an editable package

uv pip install -e .

Test against multiple Python versions using uv

make test-all

References

• NEST Simulator via its REST-based interface
• NEST Server