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tools.py
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tools.py
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# Copyright 2012-2023 Blue Brain Project / EPFL
# 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
# http://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.
"""Static tools for BluecellulabError."""
# pylint: disable=R0914, R0913
from __future__ import annotations
import io
import json
import math
import multiprocessing
import multiprocessing.pool
import os
from pathlib import Path
import sys
from typing import Any, Optional, Tuple
import warnings
import logging
import numpy as np
import bluecellulab
from bluecellulab import neuron
from bluecellulab.circuit.circuit_access import EmodelProperties
from bluecellulab.exceptions import UnsteadyCellError
logger = logging.getLogger(__name__)
VERBOSE_LEVEL = 0
ENV_VERBOSE_LEVEL: Optional[str] = None
def set_verbose(level: int = 1) -> None:
"""Set the verbose level of BluecellulabError.
Parameters
----------
level :
Verbose level, the higher the more verbosity.
Level 0 means 'completely quiet', except if some very serious
errors or warnings are encountered.
"""
bluecellulab.VERBOSE_LEVEL = level
if level <= 0:
logging.getLogger('bluecellulab').setLevel(logging.CRITICAL)
elif level == 1:
logging.getLogger('bluecellulab').setLevel(logging.ERROR)
elif level == 2:
logging.getLogger('bluecellulab').setLevel(logging.WARNING)
elif level > 2 and level <= 5:
logging.getLogger('bluecellulab').setLevel(logging.INFO)
else:
logging.getLogger('bluecellulab').setLevel(logging.DEBUG)
def set_verbose_from_env() -> None:
"""Get verbose level from environment."""
bluecellulab.ENV_VERBOSE_LEVEL = os.environ.get('BLUECELLULAB_VERBOSE_LEVEL')
if bluecellulab.ENV_VERBOSE_LEVEL is not None:
set_verbose(int(bluecellulab.ENV_VERBOSE_LEVEL))
set_verbose_from_env()
class deprecated:
"""Decorator to mark a function as deprecated."""
def __init__(self, new_function=""):
self.new_function = new_function
def __call__(self, func):
def rep_func(*args, **kwargs):
"""Replacement function."""
warnings.warn(
"Call to deprecated function {%s}. Use {%s} instead." % (
func.__name__, self.new_function),
category=DeprecationWarning)
return func(*args, **kwargs)
rep_func.__name__ = func.__name__
if func.__doc__ is None or func.__doc__ == "":
func.__doc__ = "Deprecated"
rep_func.__doc__ = func.__doc__ + "\n\n \
.. note:: Replaced by %s\n\n \
.. deprecated:: .1\n" % self.new_function
rep_func.__dict__.update(func.__dict__)
return rep_func
def load_nrnmechanisms(libnrnmech_path: str) -> None:
"""Load another shared library with NEURON mechanisms. (Created by
nrnivmodl)
Parameters
----------
libnrnmech_path: string
Path to a NEURON mechanisms file
"""
neuron.h.nrn_load_dll(libnrnmech_path)
def calculate_input_resistance(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
current_delta: float = 0.01,
) -> float:
"""Calculate the input resistance at rest of the cell."""
rest_voltage = calculate_SS_voltage(
template_path, morphology_path, template_format, emodel_properties, 0.0
)
step_voltage = calculate_SS_voltage(
template_path,
morphology_path,
template_format,
emodel_properties,
current_delta,
)
voltage_delta = step_voltage - rest_voltage
return voltage_delta / current_delta
def calculate_SS_voltage(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
step_level: float,
) -> float:
"""Calculate the steady state voltage at a certain current step.
The use of Pool is safe here since it will just run a single task.
"""
pool = multiprocessing.Pool(processes=1)
SS_voltage = pool.apply(
calculate_SS_voltage_subprocess,
[
template_path,
morphology_path,
template_format,
emodel_properties,
step_level,
],
)
pool.terminate()
return SS_voltage
def calculate_SS_voltage_subprocess(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
step_level: float,
check_for_spiking=False,
spike_threshold=-20.0,
) -> float:
"""Subprocess wrapper of calculate_SS_voltage.
This code should be run in a separate process. If check_for_spiking
is True, this function will return None if the cell spikes from
100ms to the end of the simulation indicating no steady state was
reached.
"""
cell = bluecellulab.Cell(
template_path=template_path,
morphology_path=morphology_path,
template_format=template_format,
emodel_properties=emodel_properties,
)
cell.add_ramp(500, 5000, step_level, step_level)
simulation = bluecellulab.Simulation()
simulation.run(1000, cvode=template_accepts_cvode(template_path))
time = cell.get_time()
voltage = cell.get_soma_voltage()
SS_voltage = np.mean(voltage[np.where((time < 1000) & (time > 800))])
cell.delete()
if check_for_spiking:
# check for voltage crossings
if len(np.nonzero(voltage[np.where(time > 100.0)] > spike_threshold)[0]) > 0:
raise UnsteadyCellError(
"Cell spikes from 100ms to the end of the simulation."
)
return SS_voltage
def holding_current_subprocess(v_hold, enable_ttx, cell_kwargs):
"""Subprocess wrapper of holding_current."""
cell = bluecellulab.Cell(**cell_kwargs)
if enable_ttx:
cell.enable_ttx()
vclamp = bluecellulab.neuron.h.SEClamp(0.5, sec=cell.soma)
vclamp.rs = 0.01
vclamp.dur1 = 2000
vclamp.amp1 = v_hold
simulation = bluecellulab.Simulation()
simulation.run(1000, cvode=False)
i_hold = vclamp.i
v_control = vclamp.vc
cell.delete()
return i_hold, v_control
def holding_current(
v_hold: float,
cell_id: int | tuple[str, int],
circuit_path: str | Path,
enable_ttx=False,
) -> Tuple[float, float]:
"""Calculate the holding current necessary for a given holding voltage."""
cell_id = bluecellulab.circuit.node_id.create_cell_id(cell_id)
ssim = bluecellulab.SSim(circuit_path)
cell_kwargs = ssim.fetch_cell_kwargs(cell_id)
# using a pool with NEURON here is safe since it'll run one task only
pool = multiprocessing.Pool(processes=1)
i_hold, v_control = pool.apply(
holding_current_subprocess, [v_hold, enable_ttx, cell_kwargs]
)
pool.terminate()
return i_hold, v_control
def template_accepts_cvode(template_name: str | Path) -> bool:
"""Return True if template_name can be run with cvode."""
with open(template_name, "r") as template_file:
template_content = template_file.read()
if "StochKv" in template_content:
accepts_cvode = False
else:
accepts_cvode = True
return accepts_cvode
def search_hyp_current(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: Optional[EmodelProperties],
target_voltage: float,
min_current: float,
max_current: float,
) -> float:
"""Search current necessary to bring cell to -85 mV."""
med_current = min_current + abs(min_current - max_current) / 2
new_target_voltage = calculate_SS_voltage(
template_path,
morphology_path,
template_format,
emodel_properties,
med_current,
)
logger.info("Detected voltage: %f" % new_target_voltage)
if abs(new_target_voltage - target_voltage) < 0.5:
return med_current
elif new_target_voltage > target_voltage:
return search_hyp_current(
template_path=template_path,
morphology_path=morphology_path,
template_format=template_format,
emodel_properties=emodel_properties,
target_voltage=target_voltage,
min_current=min_current,
max_current=med_current,
)
else: # new_target_voltage < target_voltage:
return search_hyp_current(
template_path=template_path,
morphology_path=morphology_path,
template_format=template_format,
emodel_properties=emodel_properties,
target_voltage=target_voltage,
min_current=med_current,
max_current=max_current,
)
def detect_hyp_current(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
target_voltage: float,
) -> float:
"""Search current necessary to bring cell to -85 mV.
Compared to using NEURON's SEClamp object, the binary search better
replicates what experimentalists use
"""
return search_hyp_current(
template_path=template_path,
morphology_path=morphology_path,
template_format=template_format,
emodel_properties=emodel_properties,
target_voltage=target_voltage,
min_current=-1.0,
max_current=0.0,
)
def detect_spike_step(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
hyp_level: float,
inj_start: float,
inj_stop: float,
step_level: float,
) -> bool:
"""Detect if there is a spike at a certain step level."""
# Here it is safe to use a pool with NEURON since it'll run one task only
pool = multiprocessing.Pool(processes=1)
spike_detected = pool.apply(
detect_spike_step_subprocess,
[
template_path,
morphology_path,
template_format,
emodel_properties,
hyp_level,
inj_start,
inj_stop,
step_level,
],
)
pool.terminate()
return spike_detected
def detect_spike_step_subprocess(
template_path: str | Path,
morphology_path: str | Path,
template_format: str,
emodel_properties: EmodelProperties | None,
hyp_level: float,
inj_start: float,
inj_stop: float,
step_level: float
) -> bool:
"""Detect if there is a spike at a certain step level."""
cell = bluecellulab.Cell(
template_path=template_path,
morphology_path=morphology_path,
template_format=template_format,
emodel_properties=emodel_properties)
cell.add_ramp(0, 5000, hyp_level, hyp_level)
cell.add_ramp(inj_start, inj_stop, step_level, step_level)
simulation = bluecellulab.Simulation()
simulation.run(int(inj_stop), cvode=template_accepts_cvode(template_path))
time = cell.get_time()
voltage = cell.get_soma_voltage()
time_step = time[np.where((time > inj_start) & (time < inj_stop))]
voltage_step = voltage[np.where((time_step > inj_start) & (time_step < inj_stop))]
spike_detected = detect_spike(voltage_step)
cell.delete()
return spike_detected
def detect_spike(voltage: np.ndarray) -> bool:
"""Detect if there is a spike in the voltage trace."""
if len(voltage) == 0:
return False
else:
return bool(np.max(voltage) > -20) # bool not np.bool_
def search_threshold_current(template_name, morphology_name, hyp_level,
inj_start, inj_stop, min_current, max_current):
"""Search current necessary to reach threshold."""
med_current = min_current + abs(min_current - max_current) / 2
logger.info("Med current %d" % med_current)
spike_detected = detect_spike_step(
template_name, morphology_name, hyp_level, inj_start, inj_stop,
med_current)
logger.info("Spike threshold detection at: %f nA" % med_current)
if abs(max_current - min_current) < .01:
return max_current
elif spike_detected:
return search_threshold_current(template_name, morphology_name,
hyp_level, inj_start, inj_stop,
min_current, med_current)
else:
return search_threshold_current(template_name, morphology_name,
hyp_level, inj_start, inj_stop,
med_current, max_current)
def detect_threshold_current(template_name, morphology_name, hyp_level,
inj_start, inj_stop):
"""Search current necessary to reach threshold."""
return search_threshold_current(template_name, morphology_name,
hyp_level, inj_start, inj_stop, 0.0, 1.0)
def calculate_SS_voltage_replay(blueconfig, gid, step_level, start_time=None,
stop_time=None, ignore_timerange=False,
timeout=600):
"""Calculate the steady state voltage at a certain current step."""
pool = multiprocessing.Pool(processes=1)
# print "Calculate_SS_voltage_replay %f" % step_level
result = pool.apply_async(calculate_SS_voltage_replay_subprocess,
[blueconfig, gid, step_level, start_time,
stop_time, ignore_timerange])
try:
output = result.get(timeout=timeout)
# (SS_voltage, (time, voltage)) = result.get(timeout=timeout)
except multiprocessing.TimeoutError:
output = (float('nan'), (None, None))
# (SS_voltage, voltage) = calculate_SS_voltage_replay_subprocess(
# blueconfig, gid, step_level)
pool.terminate()
return output
def calculate_SS_voltage_replay_subprocess(blueconfig, gid, step_level,
start_time=None, stop_time=None,
ignore_timerange=False):
"""Subprocess wrapper of calculate_SS_voltage."""
process_name = multiprocessing.current_process().name
ssim = bluecellulab.SSim(blueconfig)
if ignore_timerange:
tstart = 0
tstop = int(ssim.circuit_access.config.duration)
else:
tstart = start_time
tstop = stop_time
# print "%s: Calculating SS voltage of step level %f nA" %
# (process_name, step_level)
# print "Calculate_SS_voltage_replay_subprocess instantiating gid ..."
ssim.instantiate_gids(
[gid], add_synapses=True, add_minis=True, add_stimuli=True, add_replay=True)
# print "Calculate_SS_voltage_replay_subprocess instantiating gid done"
ssim.cells[gid].add_ramp(0, tstop, step_level, step_level)
ssim.run(t_stop=tstop)
time = ssim.get_time_trace()
voltage = ssim.get_voltage_trace(gid)
SS_voltage = np.mean(voltage[np.where(
(time < tstop) & (time > tstart))])
logger.info("%s: Calculated SS voltage for gid %d "
"with step level %f nA: %s mV" %
(process_name, gid, step_level, SS_voltage))
# print "Calculate_SS_voltage_replay_subprocess voltage:%f" % SS_voltage
return (SS_voltage, (time, voltage))
class NoDaemonProcess(multiprocessing.Process):
"""Class that represents a non-daemon process."""
# pylint: disable=R0201
def _get_daemon(self):
"""Get daemon flag."""
return False
def _set_daemon(self, value):
"""Set daemon flag."""
pass
daemon = property(_get_daemon, _set_daemon) # type:ignore
# pylint: disable=W0223, R0911
# We sub-class multiprocessing.pool.Pool instead of multiprocessing.Pool
# because the latter is only a wrapper function, not a proper class.
class NestedPool(multiprocessing.pool.Pool):
"""Class that represents a MultiProcessing nested pool."""
Process = NoDaemonProcess
# pylint: disable=R0913
def search_hyp_current_replay(blueconfig, gid, target_voltage=-80,
min_current=-1.0, max_current=0.0,
precision=.5,
max_nestlevel=10,
nestlevel=1,
start_time=500, stop_time=2000,
return_fullrange=True,
timeout=600):
"""Search current to bring cell to target_voltage in a network replay."""
process_name = multiprocessing.current_process().name
if nestlevel > max_nestlevel:
return (float('nan'), (None, None))
elif nestlevel == 1:
logger.info("%s: Searching for current to bring gid %d to %f mV" %
(process_name, gid, target_voltage))
med_current = min_current + abs(min_current - max_current) / 2
(new_target_voltage, (time, voltage)) = \
calculate_SS_voltage_replay(blueconfig, gid, med_current,
start_time=start_time,
stop_time=stop_time, timeout=timeout)
if math.isnan(new_target_voltage):
return (float('nan'), (None, None))
if abs(new_target_voltage - target_voltage) < precision:
if return_fullrange:
# We're calculating the full voltage range,
# just reusing calculate_SS_voltage_replay for this
# Variable names that start with full_ point to values that are
# related to the full voltage range
(full_SS_voltage, (full_time, full_voltage)) = \
calculate_SS_voltage_replay(
blueconfig, gid, med_current,
start_time=start_time, timeout=timeout,
ignore_timerange=True)
if math.isnan(full_SS_voltage):
return (float('nan'), (None, None))
return (med_current, (full_time, full_voltage))
else:
return (med_current, (time, voltage))
elif new_target_voltage > target_voltage:
return search_hyp_current_replay(blueconfig, gid, target_voltage,
min_current=min_current,
max_current=med_current,
precision=precision,
nestlevel=nestlevel + 1,
start_time=start_time,
stop_time=stop_time,
max_nestlevel=max_nestlevel,
return_fullrange=return_fullrange)
elif new_target_voltage < target_voltage:
return search_hyp_current_replay(blueconfig, gid, target_voltage,
min_current=med_current,
max_current=max_current,
precision=precision,
nestlevel=nestlevel + 1,
start_time=start_time,
stop_time=stop_time,
max_nestlevel=max_nestlevel,
return_fullrange=return_fullrange)
# pylint: enable=R0913
class search_hyp_function:
"""Function object."""
def __init__(self, blueconfig, **kwargs):
self.blueconfig = blueconfig
self.kwargs = kwargs
def __call__(self, gid):
return search_hyp_current_replay(self.blueconfig, gid, **self.kwargs)
class search_hyp_function_gid:
"""Function object, return a tuple (gid, results)"""
def __init__(self, blueconfig, **kwargs):
self.blueconfig = blueconfig
self.kwargs = kwargs
def __call__(self, gid):
return (
gid,
search_hyp_current_replay(
self.blueconfig,
gid,
**self.kwargs))
def search_hyp_current_replay_gidlist(blueconfig, gid_list, **kwargs):
"""Search, using bisection, for the current necessary to bring a cell to
target_voltage in a network replay for a list of gids. This function will
use multiprocessing to parallelize the task, running one gid per available
core.
Parameters
----------
blueconfig : string
Path to simulation BlueConfig
gid_list : list of integers
List of the gids
target_voltage : float
Voltage you want to bring to cell to
min_current, max_current : float
The algorithm will search in
]min_current, max_current[
precision: float
The algorithm stops when
abs(calculated_voltage - target_voltage) < precision
max_nestlevel : integer
The maximum number of nested levels the algorithm explores
start_time, stop_time : float
The time range for which the voltage is simulated
and average for comparison against target_voltage
return_fullrange: boolean
Defaults to True. Set to False if you don't want to
return the voltage in full time range of the large
simulation, but rather the time between
start_time, stop_time
Returns
-------
result: dictionary
A dictionary where the keys are gids, and the values tuples of the
form (detected_level, time_voltage).
time_voltage is a tuple of the time and voltage trace at the
current injection level (=detected_level) that matches the target
target_voltage within user specified precision.
If the algorithm reaches max_nestlevel+1 iterations without
converging to the requested precision, (nan, None) is returned
for that gid.
"""
pool = NestedPool(multiprocessing.cpu_count())
results = pool.map(search_hyp_function(blueconfig, **kwargs), gid_list)
pool.terminate()
currentlevels_timevoltagetraces = {}
for gid, result in zip(gid_list, results):
currentlevels_timevoltagetraces[gid] = result
return currentlevels_timevoltagetraces
def search_hyp_current_replay_imap(blueconfig, gid_list, timeout=600,
cpu_count=None, **kwargs):
"""Same functionality as search_hyp_current_gidlist(), except that this
function returns an unordered generator.
Loop over this generator will return the unordered results one by
one. The results returned will be of the form (gid, (current_step,
(time, voltage))) When there are results that take more that
'timeout' time to retrieve, these results will be (None, None). The
user should stop iterating the generating after receiving this
(None, None) result. In this case also probably a broke pipe error
from some of the parallel process will be shown on the stdout, these
can be ignored.
"""
if cpu_count is None:
pool = NestedPool(multiprocessing.cpu_count())
else:
pool = NestedPool(cpu_count)
results = pool.imap_unordered(search_hyp_function_gid(
blueconfig, **kwargs), gid_list)
for _ in gid_list:
try:
(gid, result) = results.next(timeout=timeout)
yield (gid, result)
except multiprocessing.TimeoutError:
pool.terminate()
yield (None, None)
pool.terminate()
class NumpyEncoder(json.JSONEncoder):
def default(self, obj):
if isinstance(obj, (np.int_, np.intc, np.intp, np.int8,
np.int16, np.int32, np.int64, np.uint8,
np.uint16, np.uint32, np.uint64)):
return int(obj)
elif isinstance(obj, (np.float_, np.float16, np.float32,
np.float64)):
return float(obj)
elif isinstance(obj, np.ndarray):
return obj.tolist()
return json.JSONEncoder.default(self, obj)
class get_stdout(list):
def __enter__(self):
self.orig_stdout = sys.stdout
sys.stdout = self.stringio = io.StringIO()
return self
def __exit__(self, *args):
self.extend(self.stringio.getvalue().splitlines())
del self.stringio
sys.stdout = self.orig_stdout
def check_empty_topology() -> bool:
"""Return true if NEURON simulator topology command is empty."""
with get_stdout() as stdout:
bluecellulab.neuron.h.topology()
return stdout == ['', '']
class Singleton(type):
"""Singleton metaclass implementation.
Source: https://stackoverflow.com/a/6798042/1935611
"""
_instances: dict[Any, Any] = {}
def __call__(cls, *args, **kwargs):
if cls not in cls._instances:
cls._instances[cls] = super(Singleton, cls).__call__(
*args, **kwargs)
else: # to run init on the same object
cls._instances[cls].__init__(*args, **kwargs)
return cls._instances[cls]