nengo-first_test.py

# https://www.nengo.ai/nengo/examples/basic/single-neuron.html

import matplotlib.pyplot as plt
import numpy as np
import nengo
from nengo.dists import Uniform
from nengo.utils.matplotlib import rasterplot


model = nengo.Network("My model")

model = nengo.Network(label="A Single Neuron")

with model:
    neuron = nengo.Ensemble(
        1,
        dimensions=1,  # Represent a scalar
        # Set intercept to 0.5
        intercepts=Uniform(-0.5, -0.5),
        # Set the maximum firing rate of the neuron to 100hz
        max_rates=Uniform(100, 100),
        # Set the neuron's firing rate to increase for positive input
        encoders=[[1]],
    )

    #****************
    # PROVIDE INPUT
    #****************
    cos = nengo.Node(lambda t: np.cos(8 * t))

    #****************
    # CONNECT ELEMENTS
    #****************
    #Connect the input signal to the neuron
    nengo.Connection(cos, neuron)

    #****************
    # PROBES
    #****************
    # The original input
    cos_probe = nengo.Probe(cos)
    # The raw spikes from the neuron
    spikes = nengo.Probe(neuron.neurons)
    # Subthreshold soma voltage of the neuron
    voltage = nengo.Probe(neuron.neurons, "voltage")
    # Spikes filtered by a 10ms post-synaptic filter
    filtered = nengo.Probe(neuron, synapse=0.01)


with nengo.Simulator(model) as sim:  # Create the simulator
    #****************
    # Run
    #****************
    sim.run(1)  # Run it for 1 second

#****************
# plot the results
#****************

# Plot the decoded output of the ensemble
plt.figure()
plt.plot(sim.trange(), sim.data[filtered])
plt.plot(sim.trange(), sim.data[cos_probe])
plt.xlim(0, 1)

# Plot the spiking output of the ensemble
plt.figure(figsize=(10, 8))
plt.subplot(221)
rasterplot(sim.trange(), sim.data[spikes])
plt.ylabel("Neuron")
plt.xlim(0, 1)

# Plot the soma voltages of the neurons
plt.subplot(222)
plt.plot(sim.trange(), sim.data[voltage][:, 0], "r")
plt.xlim(0, 1)
plt.show()