Source code for spynnaker.pyNN.models.current_sources.noisy_current_source
# Copyright (c) 2017 The University of Manchester
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import numpy
from spinn_utilities.overrides import overrides
from spinn_front_end_common.interface.ds import DataType
from spinn_front_end_common.utilities.constants import BYTES_PER_WORD
from spynnaker.pyNN.data import SpynnakerDataView
from spynnaker.pyNN.exceptions import SpynnakerException
from spynnaker.pyNN.utilities import utility_calls
from .abstract_current_source import AbstractCurrentSource, CurrentSourceIDs
class NoisyCurrentSource(AbstractCurrentSource):
"""
A noisy current source beginning at "start" and ending at "stop", with
noise simulated based on the given mean and standard deviation, and
updating every `dt` (`dt` should default to the machine time step).
"""
__slots__ = [
"__mean",
"__stdev",
"__start",
"__stop",
"__dt",
"__rng",
"__parameters",
"__parameter_types"]
def __init__(self, mean=0.0, stdev=0.0, start=0.0, stop=0.0, dt=1.0,
rng=None):
"""
:param float mean:
:param float stdev:
:param float start:
:param float stop:
:param float dt:
:param rng:
"""
# There's probably no need to actually store these as you can't
# access them directly in pynn anyway
time_convert_ms = SpynnakerDataView.get_simulation_time_step_per_ms()
self.__mean = mean
self.__stdev = stdev
self.__start = start * time_convert_ms
self.__stop = stop * time_convert_ms
self.__dt = dt * time_convert_ms
if rng is None:
seed = None
self.__rng = numpy.random.RandomState(seed)
# TODO: What happens if we pass a non-None rng?
# Error if dt is not the same as machine time step
if dt != (1 / time_convert_ms):
raise SpynnakerException(
"Only currently supported for dt = machine_time_step, here "
f"dt = {dt} and machine_time_step = {1 / time_convert_ms}")
self.__parameter_types = dict()
self.__parameter_types['mean'] = DataType.S1615
self.__parameter_types['stdev'] = DataType.S1615
self.__parameter_types['start'] = DataType.UINT32
self.__parameter_types['stop'] = DataType.UINT32
self.__parameter_types['dt'] = DataType.S1615
self.__parameter_types['seed'] = DataType.UINT32
self.__parameters = dict()
self.__parameters['mean'] = self.__mean
self.__parameters['stdev'] = self.__stdev
self.__parameters['start'] = self.__start
self.__parameters['stop'] = self.__stop
self.__parameters['dt'] = self.__dt
self.__parameters['seed'] = utility_calls.create_mars_kiss_seeds(
self.__rng)
super().__init__()
[docs]
@overrides(AbstractCurrentSource.set_parameters)
def set_parameters(self, **parameters):
for key, value in parameters.items():
if key not in self.__parameters.keys():
# throw an exception
raise SpynnakerException(f"{key} is not a parameter of {self}")
self.__parameters[key] = value
# Parameters have been set, so if multi-run then it will have been
# injected already; if not then it can just be ignored
if self.app_vertex is not None:
for m_vertex in self.app_vertex.machine_vertices:
m_vertex.set_reload_required(True)
@property
@overrides(AbstractCurrentSource.get_parameters)
def get_parameters(self):
return self.__parameters
@property
@overrides(AbstractCurrentSource.get_parameter_types)
def get_parameter_types(self):
return self.__parameter_types
@property
@overrides(AbstractCurrentSource.current_source_id)
def current_source_id(self):
return CurrentSourceIDs.NOISY_CURRENT_SOURCE.value
[docs]
@overrides(AbstractCurrentSource.get_sdram_usage_in_bytes)
def get_sdram_usage_in_bytes(self):
# 3 because the seed parameter has length 4
return (len(self.__parameters) + 3) * BYTES_PER_WORD