大约有 38,342 项符合查询结果（耗时：0.0346秒） [XML]
Pandas get topmost n records within each group
... 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.groupby('id').head(2).reset_index(drop=True) to remove the multindex and flatten the...
How to sort an array of hashes in ruby
...
Snowman
28.7k4343 gold badges161161 silver badges284284 bronze badges
answered Mar 30 '11 at 8:48
GarethGareth...
#include in .h or .c / .cpp?
...
answered Jun 8 '10 at 23:36
Brendan LongBrendan Long
47.5k1616 gold badges123123 silver badges167167 bronze badges
...
MySQL get the date n days ago as a timestamp
...
182
DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERV...
How to break a line of chained methods in Python?
...
8 Answers
8
Active
...
“’” showing on page instead of “ ' ”
...
Ensure the browser and editor are using UTF-8 encoding instead of ISO-8859-1/Windows-1252.
Or use ’.
share
|
improve this answer
|
f...
animating addClass/removeClass with jQuery
...a few bytes of space.
– Arman H
Dec 8 '15 at 4:22
add a comment
|
...
Serializing an object to JSON
...akowski
63.1k2121 gold badges133133 silver badges148148 bronze badges
answered Feb 17 '09 at 20:16
Mike_GMike_G
14.1k1111 gold bad...
Random row selection in Pandas dataframe
...
58
Something like this?
import random
def some(x, n):
return x.ix[random.sample(x.index, n)]
...
How do I start a process from C#?
...
answered Oct 8 '08 at 8:42
Andy McCluggageAndy McCluggage
33.1k1717 gold badges5656 silver badges6767 bronze badges
...