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Right way to reverse pandas.DataFrame?
...ata.Odd[idx])
You are getting an error because reversed first calls data.__len__() which returns 6. Then it tries to call data[j - 1] for j in range(6, 0, -1), and the first call would be data[5]; but in pandas dataframe data[5] means column 5, and there is no column 5 so it will throw an exceptio...
What is a word boundary in regex?
... be "identifier" characters (alnums and underscore), not as anything especially useful for English.
– hobbs
Aug 24 '09 at 21:02
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delegate keyword vs. lambda notation
... If you specify an anonymous method without specifying a parameter list at all it is compatible with any delegate type returning void and without any out parameters. Armed with this knowledge, we should be able to construct two overloads to make the expressions completely unambiguous but very differ...
How to change Vagrant 'default' machine name?
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I found the multiple options confusing, so I decided to test all of them to see exactly what they do.
I'm using VirtualBox 4.2.16-r86992 and Vagrant 1.3.3.
I created a directory called nametest and ran
vagrant init precise64 http://files.vagrantup.com/precise64.box
to generate a...
How can I connect to a Tor hidden service using cURL in PHP?
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You need to set option CURLOPT_PROXYTYPE to CURLPROXY_SOCKS5_HOSTNAME, which sadly wasn't defined in old PHP versions, circa pre-5.6; if you have earlier in but you can explicitly use its value, which is equal to 7:
curl_setopt($ch, CURLOPT_PROXYTYPE, 7...
Getting multiple keys of specified value of a generic Dictionary?
...e, perhaps maintain two dictionary mapping key->value and value->List_of_keys. If you do the latter you will trade storage for look up speed. It wouldn't take much to turn @Cybis example into such a data structure.
s...
Why would I ever use push_back instead of emplace_back?
...ob is to generate the code you wrote. The optimizing compiler's job is actually to generate the code you would have written if you were an expert on platform-specific optimizations and did not care about maintainability, just performance.
The actual difference between these two statements is that t...
Differences between Perl and PHP [closed]
...ype, of which Perl has three, and the type specifier is part of the name (called a "sigil"), so $foo is a different variable than @foo or %foo.
(related to the previous point) Perl has separate symbol table entries for scalars, arrays, hashes, code, file/directory handles and formats. Each has its o...
Python super() raises TypeError
...You have to design any methods that need to multiply-inherit (most notably __init__) to pass through arguments in a clean and sensible way, otherwise you'll get TypeErrors or worse debugging problems when someone tries to multiply-inherit using your class. Unless you've really designed to support MI...
Hash and salt passwords in C#
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Actually this is kind of strange, with the string conversions - which the membership provider does to put them into config files. Hashes and salts are binary blobs, you don't need to convert them to strings unless you want to put...