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Converting a Pandas GroupBy output from Series to DataFrame
...
g1 here is a DataFrame. It has a hierarchical index, though:
In [19]: type(g1)
Out[19]: pandas.core.frame.DataFrame
In [20]: g1.index
Out[20]:
MultiIndex([('Alice', 'Seattle'), ('Bob', 'Seattle'), ('Mallory', 'Portland'),
('Mallory', 'Seattle')], dtype=object)
...
Why does Javascript's regex.exec() not always return the same value? [duplicate]
...bal, if you call a method on the same regex object, it will start from the index past the end of the last match.
When no more matches are found, the index is reset to 0 automatically.
To reset it manually, set the lastIndex property.
reg.lastIndex = 0;
This can be a very useful feature. You...
How to calculate moving average using NumPy?
...y be is faster than FFT based methods:
EDIT Corrected an off-by-one wrong indexing spotted by Bean in the code. EDIT
def moving_average(a, n=3) :
ret = np.cumsum(a, dtype=float)
ret[n:] = ret[n:] - ret[:-n]
return ret[n - 1:] / n
>>> a = np.arange(20)
>>> moving_aver...
Display numbers with ordinal suffix in PHP
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I like your solution. Additionally if you prefer not to generate 0th modify the last line to be $abbreviation = ($number)? $number. $ends[$number % 10] : $number;
– Gavin Jackson
Feb 26 '14 at 10:02
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String's Maximum length in Java - calling length() method
..., which is 2^31 - 1 (or approximately 2 billion.)
In terms of lengths and indexing of arrays, (such as char[], which is probably the way the internal data representation is implemented for Strings), Chapter 10: Arrays of The Java Language Specification, Java SE 7 Edition says the following:
The...
Aliases in Windows command prompt
...ommand dropbox research points to the same directory as research.
As Rivenfall pointed out, it is a good idea to include a command that allows for convenient editing of the alias.cmd file. See alias above. If you are in a cmd session, enter cmd to restart cmd and reload the alias.cmd file.
When ...
How to do a GitHub pull request
...ng sure your patch is still working) will update the pull request automagically (no need to click on anything)
update that branch: if your pull request is rejected, you simply can add new commits, and/or redo your history completely: it will activate your existing pull request again.
"focus" that br...
using href links inside tag
...non graphical browser or screen reader or the page is accessed programmatically, or JavaScript is disabled) what then is the "meaning" or the "intent" of this <select> you have used for navigation? It is saying "please pick a page name" and not a lot else, certainly nothing about navigating. T...
Having issue with multiple controllers of the same name in my project
...n}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }, // Parameter defaults
new string[] { "MyCompany.MyProject.WebMvc.Controllers"}
);
This will make http://server/ go to your HomeController's Index action which is, I think, what you...
What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...sed you got so many upvotes for being wrong. A database is very good about indexes, doing the query for a specific CarID would return very fast. But if you got all the Wheels are once, you would have to search for CarID in your application, which is not indexed, this is slower. Unless you have major...