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When splitting an empty string in Python, why does split() return an empty list while split('\n') re
...ncorporates both splitting algorithms in the same tool.
People seem to mentally model field-splitting
as a single concept even though more than one algorithm is involved.
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How is the undo tree used in Vim?
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See also :h undo-redo, which lists all the commands and their usage.
There are two ways to traverse the undo tree. One is to go "back in time". g+ and g- will traverse all of the nodes in the tree in chronological or reverse-chronological order (which can...
What is a faster alternative to Python's http.server (or SimpleHTTPServer)?
... for concurrent handling of requests, instead of serialising requests.
Installation
Install node.js if you haven't already. Then use the node package manager (npm) to install the package, using the -g option to install globally. If you're on Windows you'll need a prompt with administrator permissio...
How do I insert datetime value into a SQLite database?
...ient method, but I tend to forgo strong datatypes in SQLite since they are all essentially dumped in as strings anyway.
I've written a thin C# wrapper around the SQLite library before (when using SQLite with C#, of course) to handle insertions and extractions to and from SQLite as if I were dealin...
Provisioning Profiles menu item missing from Xcode 5
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trojanfoetrojanfoe
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Efficient evaluation of a function at every cell of a NumPy array
...t be faster than the "manual" double loop iteration and assignment through all the array elements. Especially, because it stores the result to a newly created variable (and not directly to the initial input). Thanks a lot for your reply though:)
– Peter
Oct 9 '...
pretty-print JSON using JavaScript
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answered Aug 28 '11 at 10:56
user123444555621user123444555621
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Regex, every non-alphanumeric character except white space or colon
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[^a-zA-Z\d\s:]
\d - numeric class
\s - whitespace
a-zA-Z - matches all the letters
^ - negates them all - so you get - non numeric chars, non spaces and non colons
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Can dplyr package be used for conditional mutating?
...and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using na_if at the end to replace 0 with NA.
df %>%
mutate(g = 2 * (a == 2 ...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
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