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How to reorder data.table columns (without copying)
... a b c
# [1,] 1 3 0.2880365
# [2,] 2 2 0.7785115
# [3,] 3 1 0.3297416
setcolorder(x, c("c", "b", "a"))
x
# 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. T...
How to get the PATH environment-variable separator in Python?
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SilentGhostSilentGhost
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NSUserDefaults removeObjectForKey vs. setObject:nil
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14
Swift 3.0
The below answer is no longer the case when I tested this.
When set to nil the result...
Python argparse command line flags without arguments
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4 Answers
4
Active
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How to prevent browser page caching in Rails
...nse.headers["Expires"] = "Mon, 01 Jan 1990 00:00:00 GMT"
end
end
Rails 4 and older versions:
class ApplicationController < ActionController::Base
before_filter :set_cache_headers
private
def set_cache_headers
response.headers["Cache-Control"] = "no-cache, no-store"
response....
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284
Set Label's AutoSize property to False, TextAlign property to MiddleCenter and Dock property to ...
DbArithmeticExpression arguments must have a numeric common type
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247
Arithmetic with DateTime is not supported in Entity Framework 6 and earlier. You have to use Db...
How to find a parent with a known class in jQuery?
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49
Note that there is little catch: If your starting element matches query too you don't get parent element but same element instead. This ma...
UUID max character length
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174
Section 3 of RFC4122 provides the formal definition of UUID string representations. It's 36 cha...