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Is there an R function for finding the index of an element in a vector?
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The function match works on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
Fo...
Convert pandas timezone-aware DateTimeIndex to naive timestamp, but in certain timezone
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120
To answer my own question, this functionality has been added to pandas in the meantime. Starting...
What's the best way to communicate between view controllers?
...a controller, unless it's strictly "presentation" data.
Second, see page 10 of the Stanford presentation for an example of how to programmatically push a controller onto the navigation controller. For an example of how to do this "visually" using Interface Builder, take a look at this tutorial.
Th...
Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?
...y than the following to check to see if a string is nil OR has a length of 0 in Ruby?
16 Answers
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Select elements by attribute
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190
Do you mean can you select them? If so, then yes:
$(":checkbox[myattr]")
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Convert boolean to int in Java
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600
int myInt = myBoolean ? 1 : 0;
^^
PS : true = 1 and false = 0
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await vs Task.Wait - Deadlock?
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Mario Sannum
10.6k88 gold badges3434 silver badges4545 bronze badges
answered Oct 30 '12 at 14:19
Stephen ClearySte...
nServiceBus vs Mass Transit vs Rhino Service Bus vs other?
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answered Oct 23 '09 at 19:17
Udi DahanUdi Dahan
11.2k1919 silver badges3131 bronze badges
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How to get the first element of the List or Set? [duplicate]
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– HaydenKai
Sep 13 '16 at 23:10
12
Good enough if your set has only one element.
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Appending an element to the end of a list in Scala
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400
List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a comp...