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In Python how should I test if a variable is None, True or False
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a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none
– wesm
Apr 3 '15 at 21:06
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How does the extend() function work in jQuery?
I saw this in a plugin:
6 Answers
6
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pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
Create folder with batch but only if it doesn't already exist
... @jpmc26 You are right, a trailing slash does the job and is actually preferable since it works with quotes (thus allowing you to have spaces in the directory path). To distinguish between either file/directory, this will work: if exist "a" if not exist "a\" (echo "it's a file") else (echo...
Globally catch exceptions in a WPF application?
...ication where parts of it may throw exceptions at runtime. I'd like to globally catch any unhandled exception and log them, but otherwise continue program execution as if nothing happened (kinda like VB's On Error Resume Next ).
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Can a project have multiple origins?
... as you want, but you can only have one remote named "origin". The remote called "origin" is not special in any way, except that it is the default remote created by Git when you clone an existing repository. You can configure a second remote, push to/pull from that remote, and setup some branches to...
How to check if all list items have the same value and return it, or return an “otherValue” if they
If all the items in a list have the same value, then I need to use that value, otherwise I need to use an “otherValue”. I can’t think of a simple and clear way of doing this.
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Visual Studio immediate window command for Clear All
... you can use >cls, which is a predefined command alias to >Edit.ClearAll.
The MSDN article lists all predefined aliases and you can define your own, too. (For VS 2010 and earlier, custom aliases are described in a separate article, though.) Scanning through, there's a whole slew of them, some...
'UserControl' constructor with parameters in C#
Call me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two...
Does Go have “if x in” construct similar to Python?
...ion without separate methods for every single type
– Allen
May 13 '15 at 4:33
29
It could be done...