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Aggregate / summarize multiple variables per group (e.g. sum, mean)
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Where is this year() function from?
You could also use the reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 ...
Enabling markdown highlighting in Vim
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This should work to disable the end-of-line space highlighting when using the plasticboy mkd pl...
Can I pass an array as arguments to a method with variable arguments in Java?
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answered May 27 '10 at 21:58
jasonmp85jasonmp85
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EC2 instance types's exact network performance?
I cannot find exact network performance details for different EC2 instance types on Amazon. Instead, they are only saying:
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How to create full compressed tar file using Python?
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edited Dec 31 '19 at 21:45
ventaquil
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answer...
How can I increment a char?
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In Python 2.x, just use the ord and chr functions:
>>> ord('c')
99
>>> ord('c') + 1
100
>>> chr(ord('c') + 1)
'd'
>>>
Python 3.x makes this more organized and interesting, due to its clear distin...
Jackson and generic type reference
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edited Nov 12 '12 at 1:46
Jherico
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What is the difference between os.path.basename() and os.path.dirname()?
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Rename an environment with virtualenvwrapper
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How to create a directory using nerdtree
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