Source code for hysop.tools.contexts
# Copyright (c) HySoP 2011-2024
#
# This file is part of HySoP software.
# See "https://particle_methods.gricad-pages.univ-grenoble-alpes.fr/hysop-doc/"
# for further info.
#
# 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.
import os, time, sys
import numpy as np
from contextlib import contextmanager, ExitStack
[docs]
@contextmanager
def nested(*managers):
with ExitStack() as stack:
yield tuple(stack.enter_context(m) for m in managers)
[docs]
class Timer:
def __enter__(self, factor=1):
self.start = time.time()
self.factor = factor
self.end = None
self.interval = None
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self.end = time.time()
self.interval = (self.end - self.start) * self.factor
if exc_type:
raise
[docs]
@contextmanager
def printoptions(*args, **kwargs):
original = np.get_printoptions()
np.set_printoptions(*args, **kwargs)
yield
np.set_printoptions(**original)
[docs]
@contextmanager
def systrace(fn=None):
__old_trace = sys.gettrace()
def __trace(frame, event, arg):
print(f"{event} {frame.f_code.co_filename}:{frame.f_lineno}")
fn = fn or __trace
sys.settrace(fn)
yield
sys.settrace(__old_trace)
[docs]
@contextmanager
def redirect_stdout(fileobj):
old = sys.stdout
old.flush()
sys.stdout = fileobj
try:
yield fileobj
finally:
sys.stdout = old
[docs]
@contextmanager
def redirect_stderr(fileobj):
old = sys.stderr
old.flush()
sys.stderr = fileobj
try:
yield fileobj
finally:
sys.stderr = old
# See https://stackoverflow.com/questions/4675728/redirect-stdout-to-a-file-in-python/22434262#22434262
[docs]
@contextmanager
def stdout_redirected(to=os.devnull): # C-level redirection (file descriptor level)
def fileno(file_or_fd):
fd = getattr(file_or_fd, "fileno", lambda: file_or_fd)()
if not isinstance(fd, int):
raise ValueError("Expected a file (`.fileno()`) or a file descriptor")
return fd
stdout = sys.stdout
stdout_fd = fileno(stdout)
with os.fdopen(os.dup(stdout_fd), "wb") as copied:
stdout.flush()
os.dup2(fileno(to), stdout_fd)
try:
yield
finally:
stdout.flush()
os.dup2(copied.fileno(), stdout_fd)
[docs]
@contextmanager
def stderr_redirected(to=os.devnull): # C-level redirection (file descriptor level)
def fileno(file_or_fd):
fd = getattr(file_or_fd, "fileno", lambda: file_or_fd)()
if not isinstance(fd, int):
raise ValueError("Expected a file (`.fileno()`) or a file descriptor")
return fd
stderr = sys.stderr
stderr_fd = fileno(stderr)
with os.fdopen(os.dup(stderr_fd), "wb") as copied:
stderr.flush()
os.dup2(fileno(to), stderr_fd)
try:
yield
finally:
stderr.flush()
os.dup2(copied.fileno(), stderr_fd)