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Pandas dataframe get first row of each group
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1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first reco...
How do I use JDK 7 on Mac OSX?
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Oracle has released JDK 7 for OS X.
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mysql create user if not exists
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In 5.7.6 and above, you should be able to use CREATE USER
CREATE USER IF NOT EXISTS 'user'@'localhost' IDENTIFIED BY 'password';
Note that the 5.7.6 method doesn't actually grant any permissions.
If you aren't using a versio...
git rebase, keeping track of 'local' and 'remote'
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247
TL;DR;
To summarize (As Benubird comments), when:
git checkout A
git rebase B # rebase A ...
Initializing a struct to 0
...one which your coding standard mandates.
[Ref 1] Reference C99 Standard 6.7.8.21:
If there are fewer initializers in a brace-enclosed list than there are elements or members of an aggregate, or fewer characters in a string literal used to initialize an array of known size than there are ele...
Counting the Number of keywords in a dictionary in python
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edited Feb 7 '10 at 5:11
answered Feb 6 '10 at 7:41
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Is there an equivalent for the Zip function in Clojure Core or Contrib?
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Why does [5,6,8,7][1,2] = 8 in JavaScript?
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answered Sep 14 '11 at 18:17
Lightness Races in OrbitLightness Races in Orbit
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How to copy directories in OS X 10.7.3?
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Andy FrieseAndy Friese
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How to remove all rows in a numpy.ndarray that contain non-numeric values
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>>> a = np.array([[1,2,3], [4,5,np.nan], [7,8,9]])
array([[ 1., 2., 3.],
[ 4., 5., nan],
[ 7., 8., 9.]])
>>> a[~np.isnan(a).any(axis=1)]
array([[ 1., 2., 3.],
[ 7., 8., 9.]])
and reassign this to a.
Explanation: np....