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Pandas: drop a level from a multi-level column index?
...tuples([("a", "b"), ("a", "c")])
>>> df = pd.DataFrame([[1,2], [3,4]], columns=cols)
>>> df
a
b c
0 1 2
1 3 4
[2 rows x 2 columns]
>>> df.columns = df.columns.droplevel()
>>> df
b c
0 1 2
1 3 4
[2 rows x 2 columns]
...
bash HISTSIZE vs. HISTFILESIZE?
... lines.
You write 50 lines.
At the end of your 50 commands, only commands 41 to 50 are in your history list, whose size is determined by HISTSIZE=10.
You end your session.
Assuming histappend is not enabled, commands 41 to 50 are saved to your HISTFILE which now has the 10 commands it held at the ...
Logging framework incompatibility
...ixing the 1.5.6 version of the jcl bridge with the 1.6.0 version of the slf4j-api; this won't work because of a few changes in 1.6.0. Use the same versions for both, i.e. 1.6.1 (the latest). I use the jcl-over-slf4j bridge all the time and it works fine.
...
JPA: How to have one-to-many relation of the same Entity type
...ate both sides of the relationship. This is written unambiguously on page 42 of the JPA 2.0 spec:
Note that it is the application that bears responsibility for maintaining the consistency of runtime relationships—for example, for insuring that the “one” and the “many” sides of a bidir...
What is ASP.NET Identity's IUserSecurityStampStore interface?
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edited Jan 24 '17 at 14:41
niico
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How do I convert a String to an InputStream in Java?
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4 Answers
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How do I calculate the normal vector of a line segment?
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4 Answers
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How can I initialize an ArrayList with all zeroes in Java?
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432
The integer passed to the constructor represents its initial capacity, i.e., the number of ele...
Using the Underscore module with Node.js
... require("./underscore-min")
{ [Function]
_: [Circular],
VERSION: '1.1.4',
forEach: [Function],
each: [Function],
map: [Function],
inject: [Function],
(...more functions...)
templateSettings: { evaluate: /<%([\s\S]+?)%>/g, interpolate: /<%=([\s\S]+?)%>/g },
template: [F...
What does “Splats” mean in the CoffeeScript tutorial?
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