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Selecting with complex criteria from pandas.DataFrame
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Sure! Setup:
>>> import pandas as pd
>>> from random import randint
>>> df = pd.DataFrame({'A': [randint(1, 9) for x in range(10)],
'B': [randint(1, 9)*10 for x in range(10)],
'C': [randint(1, 9...
Threads vs Processes in Linux
...ter to use processes instead of threads, since Linux is very efficient in handling processes, and because there are so many problems (such as locking) associated with threads. However, I am suspicious, because it seems like threads could give a pretty big performance gain in some situations.
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Function in JavaScript that can be called only once
...y once, in each time after the first it won't be executed. I know from C++ and Java about static variables that can do the work but I would like to know if there is a more elegant way to do this?
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Accessing localhost:port from Android emulator
...ith the IP address "10.0.2.2".
This has been designed in this way by the Android team. So your webserver can perfectly run at localhost and from your Android app you can access it via "http://10.0.2.2:<hostport>".
If your emulator must access the internet through a proxy server, you can con...
PHP - Extracting a property from an array of objects
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this is the correct solution and will lead to the fact that every upcoming maintainer will be "wtf"'d :D
– Andreas Klinger
Jul 13 '09 at 11:56
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Why does “return list.sort()” return None, not the list?
... l = sorted(l.append('2')) (I just added semi-colon so you could cut/paste and run)
– JGFMK
May 30 '18 at 9:54
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JavaScript open in a new window, not tab
...,location=0,menubar=0'. You can verify it by omitting this third parameter and leaving '_blank' there as the 2nd parameter.
– user1451111
Aug 25 '17 at 4:49
1
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Is there a replacement for unistd.h for Windows (Visual C)?
...n't exist. Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'.
I know I can replace the random functions, and I'm pretty sure I can find/hack-up a getopt implementation.
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How do I delete NuGet packages that are not referenced by any project in my solution?
Somehow during the upgrade to VS2012 and .NET 4.5, I've managed to get NuGet confused. There are packages that appear in the package manager (and the packages folder) that I cannot delete (I believe they are legacy ASP.NET NuGet packages that have been replaced with new package names with the new v...
Logical Operators, || or OR?
... no "better" but the more common one is ||. They have different precedence and || would work like one would expect normally.
See also: Logical operators (the following example is taken from there):
// The result of the expression (false || true) is assigned to $e
// Acts like: ($e = (false || true...