大约有 47,000 项符合查询结果（耗时：0.0648秒） [XML]
remove None value from a list without removing the 0 value
...
10 Answers
10
Active
...
How to get the first column of a pandas DataFrame as a Series?
...ataFrame({'x' : [1, 2, 3, 4], 'y' : [4, 5, 6, 7]})
>>> df
x y
0 1 4
1 2 5
2 3 6
3 4 7
>>> s = df.ix[:,0]
>>> type(s)
<class 'pandas.core.series.Series'>
>>>
===========================================================================
UPDATE
If...
Too many 'if' statements?
...
600
If you cannot come up with a formula, you can use a table for such a limited number of outcomes...
What is the best Battleship AI?
...
+450
I second the motion to do a lot more games per match. Doing 50 games is just flipping a coin. I needed to do 1000 games to get any r...
Does the ternary operator exist in R?
...
306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a ...
How do I use a Boolean in Python?
...
Transcendence
2,07622 gold badges1818 silver badges3030 bronze badges
answered Nov 17 '09 at 12:51
Bastien LéonardBa...
Why do enum permissions often have 0, 1, 2, 4 values?
Why are people always using enum values like 0, 1, 2, 4, 8 and not 0, 1, 2, 3, 4 ?
7 Answers
...
Check if UIColor is dark or bright?
...o use is ((Red value * 299) + (Green value * 587) + (Blue value * 114)) / 1000.
share
|
improve this answer
|
follow
|
...
Android phone orientation overview including compass
...ow I think (hope) I have a better feeling for it again but I am still not 100%. I will try and explain my patchy understanding of it and hopefully people will be able to correct me if I am wrong in parts or fill in any blanks.
...
Is there a way to 'uniq' by column?
... delimiter
-k1,1 for the key field 1
Test result:
overflow@domain2.com,2009-11-27 00:58:29.793000000,xx3.net,255.255.255.0
stack2@domain.com,2009-11-27 01:05:47.893000000,xx2.net,127.0.0.1
share
|
...