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Redirecting stdout to “nothing” in python
...eference to the original sys.stdout and set it back after. For example old_stdout = sys.stdout before any of the other code, then sys.stdout = old_stdout when you are done.
– Andrew Clark
Aug 20 '14 at 21:05
...
What's the $unwind operator in MongoDB?
...owing documents:
{
"result" : [
{
"_id" : ObjectId("4e6e4ef557b77501a49233f6"),
"title" : "this is my title",
"author" : "bob",
"tags" : "fun"
},
{
"_...
Why is pow(a, d, n) so much faster than a**d % n?
... +1 that's actually what the docstring implies >>> print pow.__doc__ pow(x, y[, z]) -> number With two arguments, equivalent to x**y. With three arguments, equivalent to (x**y) % z, but may be more efficient (e.g. for longs).
– Hedde van der Heide
...
LINQ Select Distinct with Anonymous Types
...lt;T> : IEqualityComparer<T>
{
private Func<T, T, bool> _equals;
private Func<T, int> _hashCode;
public DelegateComparer(Func<T, T, bool> equals, Func<T, int> hashCode)
{
_equals= equals;
_hashCode = hashCode;
}
public bool Equ...
Elastic Search: how to see the indexed data
...Search and Rails, where some data was not indexed properly because of attr_protected. Where does Elastic Search store the indexed data? It would be useful to check if the actual indexed data is wrong.
...
How to avoid .pyc files?
...terpreter. This setting is available
to Python programs as the
sys.dont_write_bytecode variable, and
Python code can change the value to
modify the interpreter’s behaviour.
Update 2010-11-27: Python 3.2 addresses the issue of cluttering source folders with .pyc files by introducing a spe...
How to convert vector to array
...?
If you're calling an API function that expects the former, you can do do_something(&v[0], v.size()), where v is a vector of doubles. The elements of a vector are contiguous.
Otherwise, you just have to copy each element:
double arr[100];
std::copy(v.begin(), v.end(), arr);
Ensure not only...
Delete files older than 15 days using PowerShell
...n the $limit.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { !$_.PSIsContainer -and $_.CreationTime -lt $limit } | Remove-Item -Force
# Delete any empty directories left behind after deleting the old files.
Get-ChildItem -Path $path -Recurse -Force | Where-Object { $_.PSIsContainer -and...
Circular list iterator in Python
...
Or you can do like this:
conn = ['a', 'b', 'c', 'd', 'e', 'f']
conn_len = len(conn)
index = 0
while True:
print(conn[index])
index = (index + 1) % conn_len
prints a b c d e f a b c... forever
share
...
Stripping everything but alphanumeric chars from a string in Python
...ng.printable (part of the built-in string module). The use of compiled '[\W_]+' and pattern.sub('', str) was found to be fastest.
$ python -m timeit -s \
"import string" \
"''.join(ch for ch in string.printable if ch.isalnum())"
10000 loops, best of 3: 57.6 usec per loop
$ python -m tim...