# define a poisson spike-train
rate = 10 # events per time unit
length = 1.0 # one time unit
isi = numpy.random.exponential(1.0 / rate, size=(rate * length * 2,))
# spike times
t = numpy.add.accumulate(isi)
spike_times = t[t < length]
regimes = []
events = []
for i, t_spike in enumerate(spike_times):
events += [nineml.On("t>%f" % t_spike, do=nineml.SpikeOutputEvent)]
spiker = nineml.Regime(transitions=events)
c1 = nineml.Component("Spike Generator", regimes=[spiker])
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
import os
base = "spike_generator"
c1.write(base + ".xml")
c2 = nineml.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
os.system("dot -Tpng %s -o %s" % (base + ".dot", base + ".png"))
regimes = [
nineml.Regime("dv/dt = Isyn",
transitions=nineml.On(
"V>Vth",
do=["tspike = t", "V = Vrest", nineml.SpikeOutputEvent],
to=refractory - regime),
name="sub-threshold-regime"),
nineml.Regime(transitions=nineml.On("t >= tspike + trefractory",
to="sub-threshold-regime"),
name="refractory-regime")
]
ports = [nineml.ReducePort("Isyn", op="+")]
leaky_iaf = nineml.Component("deltaLIFid5", regimes=regimes, ports=ports)
# delta jump synapses
regimes = [
nineml.Regime(
"dv/dt = -g*v",
transitions=nineml.On(nineml.SpikeInputEvent, do="g+=W"),
)
]
ports = [nineml.RecvPort("W"), nineml.SendPort("Isyn = dv/dt")]
# can i even send dv/dt as a variable?
delta_syn = nineml.Component("delta_jump_id5", regimes=regimes, ports=ports)
"W -= o1*(A2_minus + A3_minus*r2)",
"r1 += 1.0", "r2 += 1.0",
nineml.EventPort("PreEventRelay",
mode="send")
]),
nineml.On(nineml.PostEvent,
do=[
"W += r1*(A2_plus + A3_plus*o2)",
"o1 += 1.0", "o2 += 1.0"
])
])
]
ports = [nineml.SendPort("W")]
c1 = nineml.Component("PfisterTripletSTDP", regimes=regimes, ports=ports)
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
import os
base = "pfister_triplet_stdp"
c1.write(base + ".xml")
c2 = nineml.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
os.system("dot -Tpng %s -o %s" % (base + ".dot", base + ".png"))
"deps_o/dt = (1-eps_o)/tau_eo",
transitions=[nineml.On(nineml.PreEvent,
do=["W -= R * A_minus * eps_r * o * (W - Wmin) / (Wmax - Wmin),
"W = max(W,W_min)",
"r += eps_r",
"eps_r = 0.0",
nineml.PreEventRelay]),
nineml.On(nineml.PostEvent,
do=["W += R*A_plus*eps_o*r*(Wmax-W)/(Wmax-Wmin)",
"W = max(W,W_max)",
"o += eps_o",
"eps_o = 0.0"])]
)]
ports = [nineml.RecvPort("R"), nineml.SendPort("W")]
c1 = nineml.Component("RmulSTDPid7", regimes=regimes, ports=ports)
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
import os
base = "RmulSTDPid7"
c1.write(base + ".xml")
c2 = nineml.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
os.system("dot -Tpng %s -o %s" % (base + ".dot", base + ".png"))
Author: Abigail Morrison, 1/2011.
"""
import nineml.abstraction_layer as nineml
regimes = [
nineml.Regime("dV/dt = (Vrest - V)/(Rm*Cm) + Isyn/Cm",
transitions=nineml.On(
"V>Vth",
do=["tspike = t", "V = Vrest", nineml.SpikeOutputEvent]),
name="sub-threshold-regime")
]
ports = [nineml.SendPort("V"), nineml.ReducePort("Isyn", op="+")]
leaky_iaf = nineml.Component("gLIFid8", regimes=regimes, ports=ports)
# alpha conductances
regimes = [
nineml.Regime(
"dg_a/dt = -g_a/tau_a",
"dg/dt = g_a - g/tau_a",
transitions=nineml.On(nineml.SpikeInputEvent, do="g+=W"),
)
]
ports = [
nineml.RecvPort("V"),
nineml.RecvPort("W"),
nineml.SendPort("Isyn = g(E-V)")
transitions=[
nineml.On(nineml.PreEvent,
do=[
"W -= lambda*alpha*W*o", "r += 1.0",
nineml.EventPort("PreEventRelay",
mode="send")
]),
nineml.On(
nineml.PostEvent,
do=["W += (lambda*w0*(weight/w0)^mu*r", "o += 1.0"])
])
]
ports = [nineml.SendPort("W")]
c1 = nineml.Component("MorrisonPowerlawSTDP", regimes=regimes, ports=ports)
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
import os
base = "morrison_powerlaw_stdp"
c1.write(base + ".xml")
c2 = nineml.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
os.system("dot -Tpng %s -o %s" % (base + ".dot", base + ".png"))
import nineml.abstraction_layer as nineml
# note: this assumes that Pre/PostEvent are the arrival times of the event
# at the synapse, i.e. after application of axonal or back-propagation delays
regimes = [
nineml.Regime("dr/dt = -r/tau_plus",
"do/dt = -o/tau_minus",
transitions=[
nineml.On(nineml.PreEvent,
do=[
"W = W - o*learning_rate*alpha*W",
"r = r + 1.0", nineml.PreEventRelay
]),
nineml.On(
nineml.PostEvent,
do=["W = W + r*learning_rate*(1-W)", "o = o + 1.0"])
],
name="basic regime")
]
# should there be an additional parameter to scale the weight?
ports = [nineml.SendPort("W")]
STDPid8 = nineml.Component("STDP_id8", regimes=regimes, ports=ports)
#"W = W - o*learning_rate*alpha*W**mu",
#"W = max(W,0.0)",
#W = W + r*learning_rate*(1-W)**mu",
#"W = min(W,1.0)",
nineml.Regime(
"dr/dt = -r/tau_plus",
"do/dt = -o/tau_minus",
transitions=[nineml.On(nineml.PreEvent,
do=["W -= W_max * A_minus * o,
"W = max(W,0.0)",
"r += 1.0",
nineml.PreEventRelay]),
nineml.On(nineml.PostEvent,
do=["W += W_max*A_plus*r",
"W = min(W,W_max)",
"o += 1.0"])]
)]
ports = [nineml.SendPort("W")]
c1 = nineml.Component("STDPid1", regimes=regimes, ports=ports)
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
import os
base = "STDPid1"
c1.write(base + ".xml")
c2 = nineml.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
os.system("dot -Tpng %s -o %s" % (base + ".dot", base + ".png"))
Hebbian Plasticity, J. Neuroscience, 23(9) 3697--3714
Author: Abigail Morrison, 1/2011.
"""
import nineml.abstraction_layer as nineml
regimes = [
nineml.Regime(transitions=nineml.On(nineml.SpikeInputEvent,
do=nineml.SpikeOutputEvent),
name="ongoing-regime")
]
linear_poiss = nineml.Component("LPNid8", regimes=regimes, ports=[])
inter_event_regime = nineml.Regime(transitions=nineml.On(
nineml.SpikeInputEvent,
do=["pfire = W/N", "p = rand()"],
to="probabilistic_regime"),
name="inter_event_regime")
probabilistic_regime = nineml.Regime(transitions=[
nineml.On("pfire >= p",
do=nineml.SpikeInputEventRelay,
to=inter_event_regime),
nineml.On("pfire < p", to=inter_event_regime)
],
name="probabilistic_regime")
name="hh_regime",
transitions=al.On("V > theta", do=[al.SpikeOutputEvent]))
parameters = [
'el', 'C', 'ek', 'ena', 'gkbar', 'gnabar', 'theta', 'gl', 'celsius'
]
ports = [
al.SendPort("V"),
al.ReducePort("Isyn", op="+"),
al.ReducePort("I", op="+"),
# "op" keyword argument determines how multiple inputs to this port are handled ?
]
c1 = al.Component("Hodgkin-Huxley-id14",
parameters=parameters,
regimes=(hh_regime, ),
aliases=aliases,
ports=ports)
# write to file object f if defined
try:
# This case is used in the test suite for examples.
c1.write(f)
except NameError:
base = "HHid14"
c1.write(base + ".xml")
c2 = al.parse(base + ".xml")
assert c1 == c2
c1.to_dot(base + ".dot")
transitions=[nineml.On("V>Vth", "set_tspike")],
events=[nineml.SpikeOutputPort("V>Vth")],
name="sub-threshold-regime"),
nineml.Union("tspike = t",
"V = Vreset",
transitions=[nineml.On("true", "refractory-regime")],
name="set_tspike"),
nineml.Union(transitions=[
nineml.On("t >= tspike + trefractory", "sub-threshold-regime")
],
name="refractory-regime")
]
ports = [nineml.Port("V"), nineml.ReducePort("Isyn", op="+")]
c1 = nineml.Component("LeakyIAF", regimes=regimes, ports=ports)
# this is a hack until 9ml defines units,
# which defines the unit of time in Brian ODE
__time_factor__ = 1. * units.ms
model = brian9ml.NineMLStateUpdater(c1,
solver=NonlinearStateUpdater,
base_regime=regimes[0])
# Initial conditions
init = {'V': 0.0, 'U': 0.0, 'Isyn': 1.0}
t_init = [init.get(x, 0.0) for x in model.state_vars]
# Threshold is 0.5 to detect a spike event on the spikeout var,
# which is 0.0 if no spike, 1.0 if spike on that clock tick.
