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How to get the first column of a pandas DataFrame as a Series?
...pandas as pd
>>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4, 5, 6, 7]})
>>> df
x y
0 1 4
1 2 5
2 3 6
3 4 7
>>> s = df.ix[:,0]
>>> type(s)
<class 'pandas.core.series.Series'>
>>>
====================================================...
show all tags in git log
...have the following situation (assuming that it points at some commit)
35805ce <--- 5b7b4ead <=== refs/tags/A
(commit) tag A
(tag)
Please also note that "git tag -f A A" (notice the absence of options forcing it to be an annotated tag) is a noop - it doesn't...
Apply a function to every row of a matrix or a data frame
..., byrow=TRUE)
R> M
[,1] [,2]
[1,] 1 2
[2,] 3 4
[3,] 5 6
R> apply(M, 1, function(x) 2*x[1]+x[2])
[1] 4 10 16
R>
This takes a matrix and applies a (silly) function to each row. You pass extra arguments to the function as fourth, fifth, ... arguments to apply().
...
Create an index on a huge MySQL production table without table locking
I need to create an index on a ~5M rows MySQL table. It is a production table, and I fear a complete block of everything if I run a CREATE INDEX statement...
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Array initializing in Scala
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Vasil RemeniukVasil Remeniuk
19.7k55 gold badges6666 silver badges8181 bronze badges
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Selecting data frame rows based on partial string match in a column
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150
I notice that you mention a function %like% in your current approach. I don't know if that's a ...
python pandas remove duplicate columns
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Jean-François Corbett
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answered Nov 5 '16 at 6:15
Gene BurinskyGene ...