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What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
When maven says “resolution will not be reattempted until the update interval of MyRepo has elapsed”
With maven, I occasionally hit an artifact that comes from some 3rd-party repo that I haven't built or included in my repository yet.
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Immutable vs Mutable types
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Almost, but not exactly. Technically, all variables are passed by reference in Python, but have a semantics more like pass by value in C. A counterexample to your analogy is if you do def f(my_list): my_list = [1, 2, 3]. With pass-by-reference in C, the val...
Getting error: Peer authentication failed for user “postgres”, when trying to get pgsql working with
....conf file (/etc/postgresql/9.1/main/pg_hba.conf*).
This line:
local all postgres peer
Should be:
local all postgres md5
* If you can't find this file, running locate pg_hba.conf should show you where ...
Check Whether a User Exists
...t, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as if already checks for the exit code. There's no need to fiddle with strings, [, $? or $():
if id "$1" &>/dev/null; then
echo 'user found...
What is the difference between String.Empty and “” (empty string)?
...ich makes string.Empty more efficient.
In version 2.0 and later of .NET, all occurrences of "" refer to the same string literal, which means "" is equivalent to .Empty, but still not as fast as .Length == 0.
.Length == 0 is the fastest option, but .Empty makes for slightly cleaner code.
See the ...
Adding new column to existing DataFrame in Python pandas
... because if you have multiple rows, and you use the assignment, it assigns all rows of the new column with that value ( in your case e) which is usually undesirable.
– Paniz
Apr 27 '19 at 22:42
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Most efficient way to remove special characters from string
I want to remove all special characters from a string. Allowed characters are A-Z (uppercase or lowercase), numbers (0-9), underscore (_), or the dot sign (.).
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Is there a NumPy function to return the first index of something in an array?
...:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your item at two locations then
array[itemindex[0][0]][itemindex[1][0]]
would be equal to your item and so woul...
How do I set the UI language in vim?
...my OS is set up in German (the standard at our office), I guess vim is actually trying to be helpfull.
15 Answers
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