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Pass column name in data.table using variable [duplicate]
...emp <- quote(list(x, v))
DT[ , eval(temp)]
# x v
# 1: b 1.52566586
# 2: b 0.66057253
# 3: b -1.29654641
# 4: a -1.71998260
# 5: a 0.03159933
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Maven dependency spring-web vs spring-webmvc
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How can we access context of an application in Robolectric?
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219
Update.
Just use for version 1.x and 2.x:
Robolectric.application;
And for version 3.x:
R...
How to fix apt-get: command not found on AWS EC2? [closed]
I installed Ubuntu 12.04 on my instance and am trying to install packages using apt-get, but I am getting the following error:
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Open URL in new window with JavaScript
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224
Use window.open():
<a onclick="window.open(document.URL, '_blank', 'location=yes,height=57...
Binding ng-model inside ng-repeat loop in AngularJS
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2 Answers
2
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Concatenate multiple result rows of one column into one, group by another column [duplicate]
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2 Answers
2
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Insert at first position of a list in Python [closed]
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2 Answers
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Creating NSData from NSString in Swift
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In Swift 3
let data = string.data(using: .utf8)
In Swift 2 (or if you already have a NSString instance)
let data = string.dataUsingEncoding(NSUTF8StringEncoding)
In Swift 1 (or if you have a swift String):
let data = (string as NSString).dataUsingEncoding(NSUTF8StringEncoding...