大约有 39,000 项符合查询结果（耗时：0.0772秒） [XML]
Applying a function to every row of a table using dplyr?
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alexwhanalexwhan
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How to slice an array in Bash
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edited Jul 24 '18 at 16:35
Nicholas Pipitone
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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 ...
Is APC compatible with PHP 5.4 or PHP 5.5?
It doesn't seem like APC has been updated to coincide with the php 5.4 release (I wish they would have included APC in PHP core like originally planned).
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Safe String to BigDecimal conversion
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Bax
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answered Sep 20 '10 at 14:54
Jeroen RosenbergJeroen Rosenberg
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