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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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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...
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...
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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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 to get a specific output iterating a hash in Ruby?
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answered Aug 4 '09 at 13:38
community wiki
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how do I insert a column at a specific column index in pandas?
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How to find the installed pandas version
...]: import pandas as pd
In [77]: pd.__version__
Out[77]: '0.12.0-933-g281dc4e'
Pandas also provides a utility function, pd.show_versions(), which reports the version of its dependencies as well:
In [53]: pd.show_versions(as_json=False)
INSTALLED VERSIONS
------------------
commit: None
python: 2...
Is there an R function for finding the index of an element in a vector?
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