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Naming returned columns in Pandas aggregate function? [duplicate]
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This will drop the outermost level from the hierarchical column index:
df = data.groupby(...)...
Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)
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What I...
How do I find out if first character of a string is a number?
... && c <= '9');
Or the slower regex solutions:
s.substring(0, 1).matches("\\d")
// or the equivalent
s.substring(0, 1).matches("[0-9]")
However, with any of these methods, you must first be sure that the string isn't empty. If it is, charAt(0) and substring(0, 1) will throw a StringIn...
Tools for analyzing performance of a Haskell program
...learn Haskell (so currently I'm a completly beginner) I came over Problem 12 . I wrote this (naive) solution:
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Delete first character of a string in Javascript
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
Intrigued by this question about infinite loops in perl: while (1) Vs. for (;;) Is there a speed difference? , I decided to run a similar comparison in python. I expected that the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the c...
Append value to empty vector in R?
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Appending to an object in a for loop causes the entire object to be copied on every iteration, ...
Rails I18n validation deprecation warning
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Important: Make sure your app is not using I18n 0.6.8, it has a bug that prevents the configura...
How can I eliminate slow resolving/loading of localhost/virtualhost (a 2-3 second lag) on Mac OS X L
...nvironments on Mac OS X Lion (brand new macbook air purchased in January 2012), I have noticed that resolving to a virtual host is very slow (around 3 seconds) the first time but after that is fast as long as I continue loading it regularly.
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