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How to validate an email address using a regular expression?
Over the years I have slowly developed a regular expression that validates MOST email addresses correctly, assuming they don't use an IP address as the server part.
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How do you match only valid roman numerals with a regular expression?
Thinking about my other problem , i decided I can't even create a regular expression that will match roman numerals (let alone a context-free grammar that will generate them)
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What do “branch”, “tag” and “trunk” mean in Subversion repositories?
I've seen these words a lot around Subversion (and I guess general repository) discussions.
I have been using SVN for my projects for the last few years, but I've never grasped the complete concept of these directories.
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Remove outline from select box in FF
Is it possible to remove the dotted line surrounding a selected item in a select element?
12 Answers
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Delete element in a slice
How does this delete trick with the append function work?
6 Answers
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How do I convert a TimeSpan to a formatted string? [duplicate]
I have two DateTime vars, beginTime and endTime. I have gotten the difference of them by doing the following:
14 Answers
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Why is address zero used for the null pointer?
In C (or C++ for that matter), pointers are special if they have the value zero: I am adviced to set pointers to zero after freeing their memory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use ...
pandas: filter rows of DataFrame with operator chaining
Most operations in pandas can be accomplished with operator chaining ( groupby , aggregate , apply , etc), but the only way I've found to filter rows is via normal bracket indexing
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Sample random rows in dataframe
I am struggling to find the appropriate function that would return a specified number of rows picked up randomly without replacement from a data frame in R language? Can anyone help me out?
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What is Bit Masking?
I am fairly new to C programming, and I encountered bit masking. Can someone explain to me the general concept and function of bit masking? Examples are much appreciated.
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