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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...
str performance in python
...tly) faster than str:
>>> Timer('str(x)', 'x=100').timeit()
0.25641703605651855
>>> Timer('"%s" % x', 'x=100').timeit()
0.2169809341430664
Do note that str is still slightly slower, as @DietrichEpp said, this is because str involves lookup and function call operations, while % c...
How do I keep a label centered in WinForms?
...
284
Set Label's AutoSize property to False, TextAlign property to MiddleCenter and Dock property to ...
DbArithmeticExpression arguments must have a numeric common type
...
247
Arithmetic with DateTime is not supported in Entity Framework 6 and earlier. You have to use Db...
How do I create a datetime in Python from milliseconds?
... |
edited May 21 '13 at 14:28
answered Apr 14 '09 at 17:12
...
Why escape_javascript before rendering a partial?
...
4 Answers
4
Active
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Failed to instantiate module [$injector:unpr] Unknown provider: $routeProvider
...
404
The ngRoute module is no longer part of the core angular.js file. If you are continuing to use...
Correct way to populate an Array with a Range in Ruby
...te an array with a range using splat,
>> a=*(1..10)
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
using Kernel Array method,
Array (1..10)
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
or using to_a
(1..10).to_a
=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
...
Regular expression to limit number of characters to 10
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edited Oct 30 '09 at 12:41
answered Oct 30 '09 at 12:10
c...