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Regular expression \p{L} and \p{N}
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\p{L} matches a single code point in the category "letter".
\p{N} matches any kind of numeric character in any script.
Source: regular-expressions.info
If you're going to work with regular expressions a lot, I'd suggest bookmarking that site, it's very useful.
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Extracting numbers from vectors of strings
...e start and capturing them
as.numeric(gsub("([0-9]+).*$", "\\1", years))
or
# pattern is to just remove _years_old
as.numeric(gsub(" years old", "", years))
or
# split by space, get the element in first index
as.numeric(sapply(strsplit(years, " "), "[[", 1))
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How do I determine scrollHeight?
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Thanks! This worked for me: var height = document.getElementById("chatLog").scrollHeight - $('#chatLog').height(); $('#chatLog').scrollTop(height);
– Brian
Sep 11 '11 at 23:09
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How are multi-dimensional arrays formatted in memory?
...rray looks like an array of arrays - it's just laid out contiguously in memory. Arrays are not the same thing as pointers, but because you can often use them pretty much interchangeably it can get confusing sometimes. The compiler keeps track properly, though, which makes everything line up nicely...
C# using streams
...rete stream classes are used to deal with other types of data than bytes. For example:
The FileStream class is used when the outside source is a file
MemoryStream is used to store data in memory
System.Net.Sockets.NetworkStream handles network data
Reader/writer streams such as StreamReader and ...
How can I correctly prefix a word with “a” and “an”?
I have a .NET application where, given a noun, I want it to correctly prefix that word with "a" or "an". How would I do that?
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Is it better to use std::memcpy() or std::copy() in terms to performance?
Is it better to use memcpy as shown below or is it better to use std::copy() in terms to performance? Why?
8 Answers
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How do I break out of a loop in Scala?
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You have three (or so) options to break out of loops.
Suppose you want to sum numbers until the total is greater than 1000. You try
var sum = 0
for (i <- 0 to 1000) sum += i
except you want to stop when (sum > 1000).
What to do? ...
What is the AppDelegate for and how do I know when to use it?
I'm just beginning to work on iPhone apps. How do I know when I should be putting stuff in AppDelegate versus a custom class? Is there a rule or any type of analogy with another programming language like Python or PHP that uses an AppDelegate like pattern?
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Should Jquery code go in header or footer?
Where is the best place to put Jquery code (or separate Jquery file)? Will pages load faster if I put it in the footer?
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