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Why can't R's ifelse statements return vectors?
...st vectors, you will get longer results:
> ifelse(c(TRUE, FALSE), c(1, 2), c(3, 4))
[1] 1 4
So ifelse is intended for the specific purpose of testing a vector of booleans and returning a vector of the same length, filled with elements taken from the (vector) yes and no arguments.
It is a comm...
DateTime.ToString(“MM/dd/yyyy HH:mm:ss.fff”) resulted in something like “09/14/2013 07.20.31.371”
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248
Is it because some culture format issue?
Yes. Your user must be in a culture where the ti...
How to get a key in a JavaScript object by its value?
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27 Answers
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How do I know that the UICollectionView has been loaded completely?
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// In viewDidLoad
[self.collectionView addObserver:self forKeyPath:@"contentSize" options:NSKeyV...
How to validate a url in Python? (Malformed or not)
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django url validation regex (source):
import re
regex = re.compile(
r'^(?:http|ftp)s?:/...
Interview question: Check if one string is a rotation of other string [closed]
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How do I import a Swift file from another Swift file?
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edited Dec 2 '17 at 6:55
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How can I clone an SQL Server database on the same server in SQL Server 2008 Express?
I have an MS SQL Server 2008 Express system which contains a database that I would like to 'copy and rename' (for testing purposes) but I am unaware of a simple way to achieve this.
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How do I know which version of Javascript I'm using?
I'm just reading this documentation about Javascript 1.2, but I'm wondering which version of Javascript is being used in the most popular browsers.
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Is there a way to do method overloading in TypeScript?
...p; typeof stringOrNumberParameter == "number")
alert("Variant #2: numberParameter = " + stringOrNumberParameter + ", stringParameter = " + stringParameter);
else
alert("Variant #1: stringParameter = " + stringOrNumberParameter);
}
}
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