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Does the ternary operator exist in R?
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thanks Joshua, your answer helped a lot, I found answer from post you mentioned stackoverflow.com/a/8792474/3019570
– Mahdi Jadaliha
Feb 3 '16 at 20:53
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How to reorder data.table columns (without copying)
... c b a
# [1,] 0.2880365 3 1
# [2,] 0.7785115 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. That is, no copy is made at all, other than temporary working memory, which is as large as one column.
so should be pretty e...
Why does direction of index matter in MongoDB?
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Fetching nodes from a BTree in order is as simple as moving along each leaf until you run out and then going up a level and down the next branch. It's O(n) Out of order it's much more CPU intensive.
– Jared Kells
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How do I specify multiple targets in my podfile for my Xcode project?
...ailable_pods
end
target 'demoTests' do
available_pods
end
Reference from : http://natashatherobot.com/cocoapods-installing-same-pod-multiple-targets/
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Responsive iframe using Bootstrap
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unable decrease height of iframe. I changed from 100% to 80% class .embed-responsive iframe. But is giving empty space. after the video. How to avoid this space.
– SatyaTNV
Aug 26 '15 at 18:38
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How do I pass multiple parameters in Objective-C?
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The text before each parameter is part of the method name. From your example, the name of the method is actually
-getBusStops:forTime:
Each : represents an argument. In a method call, the method name is split at the :s and arguments appear after the :s. e.g.
[getBusStops: arg1 f...
Filtering fiddler to only capture requests for a certain domain
... are using google chrome, be sure to use the correct process id in fiddler(from google chrome).
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Why does Convert.ToString(null) return a different value if you cast null?
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Following on from JaredPar's excellent overload resolution answer - the question remains "why does Convert.ToString(string) return null, but Convert.ToString(object) return string.Empty"?
And the answer to that is...because the docs say s...
JavaScript plus sign in front of function expression
...e (+function() { ... })() notation can never execute without errors (apart from the fact that this doesn't answer the question).
– whitequark
Nov 15 '12 at 21:21
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Use of 'use utf8;' gives me 'Wide character in print'
...single byte characters. There are four bytes in your string as you can see from this:
$ perl -E 'say join ":", map { ord } split //, "鸡\n";'
233:184:161:10
The first three bytes make up your character, the last one is the line-feed.
The call to print sends these four characters to STDOUT. Your...