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How does collections.defaultdict work?
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Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
FragmentPagerAdapter Exists Only In Android.Support.V4.App (and not Android.App)
...It's a FragmentPagerAdapter for non-support fragments.
Android Studio Installation
Please add follow Gradle dependencies
dependencies {
compile 'com.android.support:support-v13:+'
}
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What is the JavaScript equivalent of var_dump or print_r in PHP? [duplicate]
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This really is not a proper answer as this is not an inherent feature or function of JavaScript and there are innumerable scenarios where one will absolutely not have access to console.log()
– Chris Rasys
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Centering a div block without the width
...date 27 Feb 2015: My original answer keeps getting voted up, but now I normally use @bobince's approach instead.
.child { /* This is the item to center... */
display: inline-block;
}
.parent { /* ...and this is its parent container. */
text-align: center;
}
My original post for historical pur...
How to get datetime in JavaScript?
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Semantically, you're probably looking for the one-liner
new Date().toLocaleString()
which formats the date in the locale of the user.
If you're really looking for a specific way to format dates, I recommend the moment.js library....
Why does “_” (underscore) match “-” (hyphen)?
...you are in a pattern context. e.g. inside a LIKE statement. When replacing all _ with an - : UPDATE sys_file set identifier = REPLACE(identifier, '_', '-') WHERE identifier LIKE '%\_%';. Notice the escaping inside LIKE and no escaping inside REPLACE. (I find it strange though that you are not in a p...
Getting rid of all the rounded corners in Twitter Bootstrap
...global modification for a very boxy-not-round site, which is to get rid of all the rounded corners in Bootstrap...
16 Answ...
How exactly does a generator comprehension work?
... generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my_list = [1, 3, 5, 9, 2, 6]
>>> filtered_list = [item for item in my_list i...
Change column type from string to float in Pandas
...ost) any other type (even if it's not necessarily sensible to do so). Also allows you to convert to categorial types (very useful).
infer_objects() - a utility method to convert object columns holding Python objects to a pandas type if possible.
convert_dtypes() - convert DataFrame columns to the ...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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