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How to start two threads at “exactly” the same time
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4 Answers
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With bash, how can I pipe standard error into another process?
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edited Jul 1 '14 at 19:06
mmlb
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answered Mar 27 '12 at 1...
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...
What's the point of having pointers in Go?
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Rails respond_with: how does it work?
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Update for Rails 4.2+
#respond_with and ::respond_to (n.b. class method) are no longer a part of Rails. They were migrated into the third-party responders gem as of Rails 4.2 (release notes / commit dated Aug 2014). While responders is not i...
How do you work with an array of jQuery Deferreds?
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How do I write a custom init for a UIView subclass in Swift?
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edited Apr 13 '17 at 20:40
answered Jun 21 '14 at 7:00
Wo...
How to prove that a problem is NP complete?
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146
To show a problem is NP complete, you need to:
Show it is in NP
In other words, given some info...
How does a garbage collector avoid an infinite loop here?
... Richter in the second edition of CLR via C# (yes I need to update):
Page 478
For (The CLR is shutting down) each Finalize method is given approximately two seconds to return. If a Finalize method doesn't return within two seconds, the CLR just kills the process - no more Finalize methods are c...
Do I need a content-type header for HTTP GET requests?
...ipient MAY either assume a media type of "application/octet-stream" ([RFC2046], Section 4.5.1) or examine the data to determine its type.
It means that the Content-Type HTTP header should be set only for PUT and POST requests.
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