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What is the AppDelegate for and how do I know when to use it?
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4 Answers
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How to expire session due to inactivity in Django?
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44
Here's an idea... Expire the session on browser close with the SESSION_EXPIRE_AT_BROWSER_CLOSE ...
Groovy: what's the purpose of “def” in “def x = 0”?
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Ted NaleidTed Naleid
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How do I use Node.js Crypto to create a HMAC-SHA1 hash?
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answered Sep 20 '11 at 4:38
Ricardo TomasiRicardo Tomasi
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Can jQuery get all CSS styles associated with an element?
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342
A couple years late, but here is a solution that retrieves both inline styling and external sty...
Does setting Java objects to null do anything anymore?
...les.
– Neil Coffey
Mar 28 '15 at 22:40
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How to drop columns by name in a data frame
... function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x y
1 1 2
2 2 3
3 3 4...
Can I have an IF block in DOS batch file?
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141
You can indeed place create a block of statements to execute after a conditional. But you have ...
How to run a background task in a servlet based web application?
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answered Jan 14 '11 at 13:45
BalusCBalusC
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