from nengo.base import NengoObject, NengoObjectParam, ObjView
from nengo.config import Config
from nengo.connection import Connection, LearningRule
from nengo.exceptions import ValidationError
from nengo.params import Default, ConnectionDefault, NumberParam, Parameter, StringParam
from nengo.solvers import SolverParam
from nengo.synapses import SynapseParam
class TargetParam(NengoObjectParam):
def coerce(self, probe, target):
obj = target.obj if isinstance(target, ObjView) else target
if not hasattr(obj, "probeable"):
raise ValidationError(
"Type %r is not probeable" % type(obj).__name__,
attr=self.name,
obj=probe,
)
# do this after; better to know that type is not Probable first
if isinstance(obj, LearningRule):
# TODO: this special case should be able to be removed with #1310
return Parameter.coerce(self, probe, target)
else:
return super().coerce(probe, target)
class AttributeParam(StringParam):
coerce_defaults = False
def coerce(self, probe, attr):
value = super().coerce(probe, attr)
if attr not in probe.obj.probeable:
raise ValidationError(
"Attribute %r is not probeable on %s.\n"
"Probeable attributes: %s" % (attr, probe.obj, probe.obj.probeable),
attr=self.name,
obj=probe,
)
return value
class ProbeSolverParam(SolverParam):
def coerce(self, conn, solver):
if solver is ConnectionDefault:
solver = Config.default(Connection, "solver")
solver = super().coerce(conn, solver)
if solver is not None and solver.weights:
raise ValidationError(
"weight solvers only work for ensemble to "
"ensemble connections, not probes",
attr=self.name,
obj=conn,
)
return solver
[docs]class Probe(NengoObject):
"""A probe is an object that collects data from the simulation.
This is to be used in any situation where you wish to gather simulation
data (spike data, represented values, neuron voltages, etc.) for analysis.
Probes do not directly affect the simulation.
All Nengo objects can be probed (except Probes themselves).
Each object has different attributes that can be probed.
To see what is probeable for each object, print its
``probeable`` attribute.
.. testcode::
with nengo.Network():
ens = nengo.Ensemble(10, 1)
print(ens.probeable)
.. testoutput::
('decoded_output', 'input', 'scaled_encoders')
Parameters
----------
target : Ensemble, Neurons, Node, or Connection
The object to probe.
attr : str, optional
The signal to probe. Refer to the target's ``probeable`` list for
details. If None, the first element in the ``probeable`` list
will be used.
sample_every : float, optional
Sampling period in seconds. If None, the ``dt`` of the simluation
will be used.
synapse : Synapse, optional
A synaptic model to filter the probed signal.
solver : Solver, optional
`~nengo.solvers.Solver` to compute decoders
for probes that require them.
label : str, optional
A name for the probe. Used for debugging and visualization.
seed : int, optional
The seed used for random number generation.
Attributes
----------
attr : str or None
The signal that will be probed. If None, the first element of the
target's ``probeable`` list will be used.
sample_every : float or None
Sampling period in seconds. If None, the ``dt`` of the simluation
will be used.
solver : Solver or None
`~nengo.solvers.Solver` to compute decoders. Only used for probes
of an ensemble's decoded output.
synapse : Synapse or None
A synaptic model to filter the probed signal.
target : Ensemble, Neurons, Node, or Connection
The object to probe.
"""
target = TargetParam("target", nonzero_size_out=True)
attr = AttributeParam("attr", default=None, optional=True)
sample_every = NumberParam("sample_every", default=None, optional=True, low=1e-10)
synapse = SynapseParam("synapse", default=None, optional=True)
solver = ProbeSolverParam("solver", default=ConnectionDefault)
_param_init_order = ["target"]
def __init__(
self,
target,
attr=None,
sample_every=Default,
synapse=Default,
solver=Default,
label=Default,
seed=Default,
):
super().__init__(label=label, seed=seed)
self.target = target
self.attr = attr if attr is not None else self.obj.probeable[0]
self.sample_every = sample_every
self.synapse = synapse
self.solver = solver
def __repr__(self):
return "<Probe%s at 0x%x of '%s' of %s>" % (
"" if self.label is None else ' "%s"' % self.label,
id(self),
self.attr,
self.target,
)
def __str__(self):
return "<Probe%s of '%s' of %s>" % (
"" if self.label is None else ' "%s"' % self.label,
self.attr,
self.target,
)
@property
def obj(self):
"""(Nengo object) The underlying Nengo object target."""
return self.target.obj if isinstance(self.target, ObjView) else self.target
@property
def size_in(self):
"""(int) Dimensionality of the probed signal."""
return self.target.size_out
@property
def size_out(self):
"""(int) Cannot connect from probes, so always 0."""
return 0
@property
def slice(self):
"""(slice) The slice associated with the Nengo object target."""
return self.target.slice if isinstance(self.target, ObjView) else None
