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regex for zip-code
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^\d{5}(?:[-\s]\d{4})?$
^ = Start of the string.
\d{5} = Match 5 digits (for condition 1, 2, 3)
(?:…) = Grouping
[-\s] = Match a space (for condition 3) or a hyphen (for condition 2)
\d{4} = Match 4 digits (for condition 2, 3...
How to select .NET 4.5.2 as a target framework in Visual Studio
I have installed .NET Framework 4.5.2 on Windows 8.1. But in Visual Studio 2013 I do not see the .NET Framework 4.5.2 option (see screenshot). How do I target my project for .NET 4.5.2?
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Applying a function to every row of a table using dplyr?
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alexwhanalexwhan
13.8k55 gold badges4545 silver badges6464 bronze badges
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How to slice an array in Bash
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edited Jul 24 '18 at 16:35
Nicholas Pipitone
3,33511 gold badge1717 silver badges3333 bronze badges
ans...
Installing specific laravel version with composer create-project
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edited Apr 14 '15 at 13:14
answered May 20 '14 at 8:15
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Try-finally block prevents StackOverflowError
...s O(2^N) where N is the maximum stack depth.
Imagine the maximum depth is 5
foo() calls
foo() calls
foo() calls
foo() calls
foo() which fails to call foo()
finally calls
foo() which fails to call foo()
finally
foo() cal...
How to filter a dictionary according to an arbitrary condition function?
...e a dict comprehension:
{k: v for k, v in points.iteritems() if v[0] < 5 and v[1] < 5}
And in Python 3:
{k: v for k, v in points.items() if v[0] < 5 and v[1] < 5}
share
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improve th...
Get the cartesian product of a series of lists?
... 2.6.
import itertools
somelists = [
[1, 2, 3],
['a', 'b'],
[4, 5]
]
for element in itertools.product(*somelists):
print(element)
Which is the same as,
for element in itertools.product([1, 2, 3], ['a', 'b'], [4, 5]):
print(element)
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What are the differences between json and simplejson Python modules?
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wim
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answered Apr 3 '09 at 6:59
Devin JeanpierreDevin Jeanpierre
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How to drop columns by name in a data frame
...exing or the subset function. For example :
R> df <- data.frame(x=1:5, y=2:6, z=3:7, u=4:8)
R> df
x y z u
1 1 2 3 4
2 2 3 4 5
3 3 4 5 6
4 4 5 6 7
5 5 6 7 8
Then you can use the which function and the - operator in column indexation :
R> df[ , -which(names(df) %in% c("z","u"))]
x ...