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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
convert a JavaScript string variable to decimal/money
...vaScript doesn't have an integer type. It only has a Number type which are all stored internally as 64bit floating point numbers. Your point is valid for other languages that do have integer types such as C#, C++, but not really for JavaScript.
– Simon Brangwin
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How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
Is there a way to call a block with a primitive parameter after a delay, like using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
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Standard alternative to GCC's ##__VA_ARGS__ trick?
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It is possible to avoid the use of GCC's ,##__VA_ARGS__ extension if you are willing to accept some hardcoded upper limit on the number of arguments you can pass to your variadic macro, as described in Richard Hansen's answer to this question. If you do not want to hav...
AngularJS performs an OPTIONS HTTP request for a cross-origin resource
...s-Origin Resource Sharing standard works by adding new HTTP
headers that allow servers to describe the set of origins that are
permitted to read that information using a web browser. Additionally,
for HTTP request methods that can cause side-effects on user data (in
particular; for HTTP meth...
Regular expression to get a string between two strings in Javascript
... capture inside parenthesis):
cow(.*)milk
No lookaheads are needed at all.
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Can I mix MySQL APIs in PHP?
...where. (Not sure whether plain old resources do that, but objects can actually take advantage of RAII to a not-insignificant degree.)
– cHao
Jul 5 '13 at 23:54
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HorizontalScrollView within ScrollView Touch Handling
...talScrollView block that has features that can be scrolled through horizontally. I've added an ontouchlistener to the horizontalscrollview to handle touch events and force the view to "snap" to the closest image on the ACTION_UP event.
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...ch element of a vector or data frame is a duplicate of an element with a smaller subscript. So if rows 3, 4, and 5 of a 5-row data frame are the same, duplicated will give me the vector
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How to work around the stricter Java 8 Javadoc when using Maven
...lt;table summary=""> trick still works on JDK8. (just tested on jdk1.8.0_201)
– peterh
Feb 17 '19 at 8:29
@peterh I...