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Pandas get topmost n records within each group
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Did you try df.groupby('id').head(2)
Ouput generated:
>>> df.groupby('id').head(2)
id 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 nee...
How can you detect the version of a browser?
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27 Answers
27
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SQL Server: Filter output of sp_who2
Under SQL Server, is there an easy way to filter the output of sp_who2? Say I wanted to just show rows for a certain database, for example.
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What is the difference between int, Int16, Int32 and Int64?
What is the difference between int , System.Int16 , System.Int32 and System.Int64 other than their sizes?
10 Answers
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Slicing of a NumPy 2d array, or how do I extract an mxm submatrix from an nxn array (n>m)?
...rray. For this example let us say the array is 4x4 and I want to extract a 2x2 array from it.
7 Answers
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nonlocal keyword in Python 2.x
I'm trying to implement a closure in Python 2.6 and I need to access a nonlocal variable but it seems like this keyword is not available in python 2.x. How should one access nonlocal variables in closures in these versions of python?
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Ruby on Rails and Rake problems: uninitialized constant Rake::DSL
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answered May 22 '11 at 4:11
Caley WoodsCaley Woods
4,62944 gold badges2626 silver badges3636 bronze badges
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Write a function that returns the longest palindrome in a given string
I thought of a solution but it runs in O(n^2) time
22 Answers
22
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xkcd style graphs in MATLAB
...plot, but you will end up with an image, not an editable plot.
I'll show #2 first, and my attempt at #1 below (if you like #1 better, look at Rody's solution!).
This solution relies on two key functions: EXPORT_FIG from the file exchange to get an anti-aliased screenshot, and IMTRANSFORM to get ...
“for loop” with two variables? [duplicate]
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201
If you want the effect of a nested for loop, use:
import itertools
for i, j in itertools.prod...