大约有 41,100 项符合查询结果（耗时：0.0514秒） [XML]
What does -> mean in Python function definitions?
I've recently noticed something interesting when looking at Python 3.3 grammar specification :
7 Answers
...
How do I append one string to another in Python?
...hon -m timeit -s"s=''" "for i in xrange(10):s+='a'"
1000000 loops, best of 3: 1.85 usec per loop
$ python -m timeit -s"s=''" "for i in xrange(100):s+='a'"
10000 loops, best of 3: 16.8 usec per loop
$ python -m timeit -s"s=''" "for i in xrange(1000):s+='a'"
10000 loops, best of 3: 158 usec per loop
$...
Remove duplicated rows
...only need the first three columns
deduped.data <- unique( yourdata[ , 1:3 ] )
# the fourth column no longer 'distinguishes' them,
# so they're duplicates and thrown out.
share
|
improve this an...
How do I convert a float number to a whole number in JavaScript?
...74099 900719925474099 900719925474099
value | 0 // 858993459 858993459 858993459
~~value // 858993459 858993459 858993459
value >> 0 // 858993459 858993459 858993459
value >>> 0 ...
Speed up the loop operation in R
...
438
Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where...
while (1) Vs. for (;;) Is there a speed difference?
...1 <0> enter ->2
2 <;> nextstate(main 2 -e:1) v ->3
9 <2> leaveloop vK/2 ->a
3 <{> enterloop(next->8 last->9 redo->4) v ->4
- <@> lineseq vK ->9
4 <;> nextstate(main 1 -e:1) v ->5
7 <@> ...
Returning first x items from array
...nittlknittl
184k4242 gold badges255255 silver badges306306 bronze badges
1
...
How do you rename a table in SQLite 3.0?
How do you rename a table in SQLite 3.0?
2 Answers
2
...
How to return multiple lines JSX in another return statement in React?
... the tags as function calls (see docs). Then the first one becomes:
{[1,2,3].map(function (n) {
return React.DOM.p(...);
})}
And the second one:
{[1,2,3].map(function (n) {
return (
React.DOM.h3(...)
React.DOM.p(...)
)
})}
It should now be clear that the second snippet doesn't re...
Is inject the same thing as reduce in ruby?
... |
edited May 9 '14 at 7:03
answered Dec 11 '12 at 3:44
Zac...