"""
Utility objects used throughout the code base.
"""
import logging
import re
import subprocess
import sys
import threading
import time
from nengo.exceptions import SimulationError
import numpy as np
import progressbar
import tensorflow as tf
logger = logging.getLogger(__name__)
# check if GPU support is available
# note: we run this in a subprocess because list_physical_devices()
# will fix certain process-level TensorFlow configuration
# options the first time it is called
tf_gpu_installed = not subprocess.call(
[
sys.executable,
"-c",
"import sys; "
"import tensorflow as tf; "
"sys.exit(len(tf.config.list_physical_devices('GPU')) == 0)",
]
)
[docs]def sanitize_name(name):
"""
Remove illegal TensorFlow name characters from string.
Valid TensorFlow name characters are ``[A-Za-z0-9_.\\-/]``
Parameters
----------
name : str
Name to be sanitized
Returns
-------
sanitized : str
Sanitized name
"""
if not isinstance(name, str):
name = str(name)
name = name.replace(" ", "_")
name = name.replace(":", "_")
valid_exp = re.compile(r"[A-Za-z0-9_.\-/]")
return "".join([c for c in name if valid_exp.match(c)])
[docs]def function_name(func, sanitize=True):
"""
Get the name of the callable object ``func``.
Parameters
----------
func : callable
Callable object (e.g., function, callable class)
sanitize : bool
If True, remove any illegal TensorFlow name characters from name
Returns
-------
name : str
Name of ``func`` (optionally sanitized)
"""
name = getattr(func, "__name__", func.__class__.__name__)
if sanitize:
name = sanitize_name(name)
return name
[docs]def align_func(output_dtype):
"""
Decorator that ensures the output of ``func`` is a valid
`~numpy.ndarray` with the given dtype.
Parameters
----------
output_dtype : str or ``tf.DType`` or `~numpy.dtype`
Desired dtype of function output(s)
Raises
------
``nengo.exceptions.SimulationError``
If the function returns ``None`` or a non-finite value.
"""
if isinstance(output_dtype, tf.DType):
output_dtype = output_dtype.as_numpy_dtype
def apply_align(func):
def aligned_func(*args):
output = func(*args)
if output is None:
raise SimulationError(
"Function %r returned None" % function_name(func, sanitize=False)
)
try:
if not np.all(np.isfinite(output)):
raise SimulationError(
"Function %r returned invalid value %r"
% (function_name(func, sanitize=False), output)
)
except (TypeError, ValueError):
raise SimulationError(
"Function %r returned a value %r of invalid type %r"
% (function_name(func, sanitize=False), output, type(output))
)
output = np.asarray(output, dtype=output_dtype)
return output
return aligned_func
return apply_align
class MessageBar(progressbar.BouncingBar):
"""
ProgressBar widget for progress bars with possibly unknown duration.
Parameters
----------
msg : str
A message to be displayed in the middle of the progress bar
finish_msg : str
A message to be displayed when the progress bar is finished
"""
def __init__(self, msg="", finish_msg="", **kwargs):
super().__init__(**kwargs)
self.msg = msg
self.finish_msg = finish_msg
def __call__(self, progress, data, width):
if progress.end_time:
return self.finish_msg
if progress.max_value is progressbar.UnknownLength:
bar = progressbar.BouncingBar
else:
bar = progressbar.Bar
line = bar.__call__(self, progress, data, width)
if data["percentage"] is None:
msg = self.msg
else:
msg = "%s (%d%%)" % (self.msg, data["percentage"])
offset = width // 2 - len(msg) // 2
return line[:offset] + msg + line[offset + len(msg) :]
[docs]class ProgressBar(progressbar.ProgressBar): # pylint: disable=too-many-ancestors
"""
Handles progress bar display for some tracked process.
Parameters
----------
present : str
Description of process in present (e.g., "Simulating")
past : str
Description of process in past (e.g., "Simulation")
max_value : int or None
The maximum number of steps in the tracked process (or ``None`` if
the maximum number of steps is unknown)
Notes
-----
Launches a separate thread to handle the progress bar display updates.
"""
def __init__(self, present="", past=None, max_value=1, **kwargs):
self.present = present
self.sub_bar = None
self.finished = None
if past is None:
past = present
self.msg_bar = MessageBar(msg=present, finish_msg="%s finished in" % past)
widgets = [self.msg_bar, " "]
if max_value is None:
widgets.append(progressbar.Timer(format="%(elapsed)s"))
else:
widgets.append(
progressbar.ETA(format="ETA: %(eta)s", format_finished="%(elapsed)s")
)
def update_thread():
while not self.finished:
if self.sub_bar is None or self.sub_bar.finished:
self.update()
time.sleep(0.001)
self.thread = threading.Thread(target=update_thread)
self.thread.daemon = True
if max_value is None:
max_value = progressbar.UnknownLength
super().__init__(
poll_interval=0.1,
widgets=widgets,
fd=sys.stdout,
max_value=max_value,
**kwargs,
)
[docs] def start(self, **kwargs):
"""Start tracking process, initialize display."""
super().start(**kwargs)
self.finished = False
self.thread.start()
return self
[docs] def finish(self, **kwargs):
"""Stop tracking process, finish display."""
if self.sub_bar is not None and self.sub_bar.finished is False:
self.sub_bar.finish()
self.finished = True
self.thread.join()
super().finish(**kwargs)
[docs] def step(self):
"""
Advance the progress bar one step.
"""
self.value += 1
[docs] def sub(self, msg=None, **kwargs):
"""
Creates a new progress bar for tracking a sub-process.
Parameters
----------
msg : str
Description of sub-process
"""
if self.sub_bar is not None and self.sub_bar.finished is False:
self.sub_bar.finish()
self.sub_bar = SubProgressBar(
present="%s: %s" % (self.present, msg) if msg else self.present, **kwargs
)
return self.sub_bar
@property
def max_steps(self):
"""
Alias for max_value to allow this to work with Nengo progress bar
interface.
"""
return self.max_value
@max_steps.setter
def max_steps(self, n):
self.max_value = n
def __enter__(self):
super().__enter__()
return self.start()
def __next__(self):
"""Wraps an iterable using this progress bar."""
try:
assert self.start_time is not None
self.step()
value = next(self._iterable)
return value
except StopIteration:
self.finish()
raise
[docs]class SubProgressBar(ProgressBar): # pylint: disable=too-many-ancestors
"""
A progress bar representing a sub-task within an overall progress bar.
"""
[docs] def finish(self, **kwargs):
"""Finishing a sub-progress bar doesn't start a new line."""
super().finish(end="\r", **kwargs)
[docs]class NullProgressBar(progressbar.NullBar): # pylint: disable=too-many-ancestors
"""
A progress bar that does nothing.
Used to replace ProgressBar when we want to disable output.
"""
def __init__(self, present="", past=None, max_value=1, **kwargs):
super().__init__(max_value=max_value, **kwargs)
[docs] def sub(self, *args, **kwargs):
"""
Noop for creating a sub-progress bar.
"""
return self
[docs] def step(self, **kwargs):
"""
Noop for incrementing the progress bar.
"""
