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Convert UNIX epoch to Date object
...16:32:00 CST"
R> anydate(1352068320)
[1] "2012-11-04"
R>
Note how all this works without any format or origin arguments.
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Turn Pandas Multi-Index into column
...he parameter is drop=False (which will keep the index values as columns).
All you have to do add .reset_index(inplace=True) after the name of the DataFrame:
df.reset_index(inplace=True)
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Java `final` method: what does it promise?
...method can't be overridden (for object scope) or hidden (for static). This allows the original developer to create functionality that cannot be changed by subclasses, and that is all the guarantee it provides.
This means that if the method relies on other customizable components like non-public fie...
Is pass-by-value a reasonable default in C++11?
...by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory management (in the event that ...
WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED
...If you use the set transaction isolation level statement, it will apply to all the tables in the connection, so if you only want a nolock on one or two tables use that; otherwise use the other.
Both will give you dirty reads. If you are okay with that, then use them. If you can't have dirty reads,...
How to create a zip archive of a directory in Python?
...e. The documentation tells you what functions are available, but doesn't really explain how you can use them to zip an entire directory. I think it's easiest to explain with some example code:
#!/usr/bin/env python
import os
import zipfile
def zipdir(path, ziph):
# ziph is zipfile handle
f...
How to overload __init__ method based on argument type?
Let's say I have a class that has a member called data which is a list.
10 Answers
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How to fire AJAX request Periodically?
...the page after every 5 seconds. But I want to do it using jQuery and AJAX call. Is it possible?
4 Answers
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ngClass style with dash in key
I hope this saves someone a headache with styles that use dashes, especially since bootstrap has become so popular.
3 Answe...
Change a column type from Date to DateTime during ROR migration
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This answer is only partially correct, you can not use change_column inside change even on rails 4 or down migration will not work. You should use up/down no matter the version of rails.
– Alan Peabody
Jul 18 '1...