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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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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...
Prevent text selection after double click
...getSelection) {
var sel = window.getSelection();
sel.removeAllRanges();
}
}
You can also apply these styles to the span for all non-IE browsers and IE10:
span.no_selection {
user-select: none; /* standard syntax */
-webkit-user-select: none; /* webkit (safari, chrome) ...
Rails: Open link in new tab (with 'link_to')
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The target: :_blank parameter should be a parameter of link_to, whereas you put it in image_tag parameters. Modify your code like this:
<%= link_to image_tag("facebook.png", class: :facebook_icon, alt: "Facebook"), "http://www.facebo...
Add a new item to a dictionary in Python [duplicate]
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default_data['item3'] = 3
Easy as py.
Another possible solution:
default_data.update({'item3': 3})
which is nice if you want to insert multiple items at once.
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Sorting a tab delimited file
...u probably want
sort -k4nr file.txt
to sort file.txt by column 4 numerically in reverse order. (Though the data in the question has even 5 fields so the last field would be index 5.)
share
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impr...
Do I need to close() both FileReader and BufferedReader?
...s javadoc's don't say whether or not it closes it's wrapped Reader or not. All it says related to that is Closes the stream and releases any system resources associated with it. which is not explicit enough to say that it does or does not close the resource. 'Release the resource' may just as well b...
Can an Option in a Select tag carry multiple values?
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I was actually wondering this today, and I achieved it by using the php explode function, like this:
HTML Form (in a file I named 'doublevalue.php':
<form name="car_form" method="post" action="doublevalue_action.php">
...
'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...
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...