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Python creating a dictionary of lists
... 'a' is not defined
– S Andrew
Nov 14 '18 at 13:18
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Pandas get topmost n records within each group
... value
id
1 0 1 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 remo...
How to count the frequency of the elements in an unordered list?
...tertools package if the list is an ordered list.
a = [1,1,1,1,2,2,2,2,3,3,4,5,5]
from itertools import groupby
[len(list(group)) for key, group in groupby(a)]
Output:
[4, 4, 2, 1, 2]
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im...
Remove duplicated rows using dplyr
...rame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need the dummy z variable and will just be
able to write row_number() == 1)
I've also been thinking about adding a slice() function that would
work like:
df %>% group_by(x, y) %>% slice(fro...
What are the GCC default include directories?
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MySQL: What's the difference between float and double?
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answered Jan 29 '10 at 9:04
Daniel VassalloDaniel Vassallo
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What is the difference between Gemfile and Gemfile.lock in Ruby on Rails
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edited Mar 29 '18 at 14:02
cori
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answered Aug...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...True is reassignable:
Python 2.7 (r27:82508, Jul 3 2010, 21:12:11)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> True = 4
>>> True
4
In Python 3.x it truly becomes a keyword and a real constant:
Pyth...
how do I insert a column at a specific column index in pandas?
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How to get a specific output iterating a hash in Ruby?
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answered Aug 4 '09 at 13:38
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