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How do I sort one vector based on values of another
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answered Oct 14 '09 at 21:47
Ian FellowsIan Fellows
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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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Could not find com.google.android.gms:play-services:3.1.59 3.2.25 4.0.30 4.1.32 4.2.40 4.2.42 4.3.23
... place stopped working:
https://plus.google.com/+AndroidDevelopers/posts/4Yhpn6p9icf
12 Answers
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Maximum number of characters using keystrokes A, Ctrl+A, Ctrl+C and Ctrl+V
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14 Answers
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How to use the 'sweep' function
...o the 2nd, etc. of the matrix you defined, you will do:
sweep (M, 1, c(1: 4), "+")
I frankly did not understand the definition in the R documentation either, I just learned by looking up examples.
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Index all *except* one item in python
... 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays. If you replace [] with (), b will be an iterator inst...
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...
How to get the first column of a pandas DataFrame as a Series?
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143
>>> import pandas as pd
>>> df = pd.DataFrame({'x' : [1, 2, 3, 4], 'y' : [4, ...
What is the full path to the Packages folder for Sublime text 2 on Mac OS Lion
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Rob CowieRob Cowie
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How to reorder data.table columns (without copying)
... a b c
# [1,] 1 3 0.2880365
# [2,] 2 2 0.7785115
# [3,] 3 1 0.3297416
setcolorder(x, c("c", "b", "a"))
x
# c b a
# [1,] 0.2880365 3 1
# [2,] 0.7785115 2 2
# [3,] 0.3297416 1 3
From ?setcolorder:
In data.table parlance, all set* functions change their input by reference. T...