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Relative frequencies / proportions with dplyr
...ltiple variables, each summary peels off one level of the grouping. That makes it easy to progressively roll-up a dataset.
Thus, after the summarise, the last grouping variable specified in group_by, 'gear', is peeled off. In the mutate step, the data is grouped by the remaining grouping variable(...
Is there a way to access an iteration-counter in Java's for-each loop?
...ll, and may in fact be something not at all based on indexes (such as a linked list).
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What is the purpose of a plus symbol before a variable?
this really sounds like a simple question but I had no luck searching. what does the +d in
3 Answers
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How to determine the current shell I'm working on
How can I determine the current shell I am working on?
24 Answers
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How to open a file for both reading and writing?
...d reopening:
with open(filename, "r+") as f:
data = f.read()
f.seek(0)
f.write(output)
f.truncate()
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Regarding 'main(int argc, char *argv[])' [duplicate]
...l where an user could type cat file. Here the word cat is a program that takes a file and outputs it to standard output (stdout).
The program receives the number of arguments in argc and the vector of arguments in argv, in the above the argument count would be two (The program name counts as the fi...
adb shell command to make Android package uninstall dialog appear
...ng this command:
adb shell am start -a android.intent.action.DELETE -d package:<your app package>
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How to make IPython notebook matplotlib plot inline
I am trying to use IPython notebook on MacOS X with Python 2.7.2 and IPython 1.1.0.
10 Answers
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List of tuples to dictionary
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Sven MarnachSven Marnach
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How to determine the number of days in a month in SQL Server?
...he specified month:
datediff(day, @date, dateadd(month, 1, @date))
To make it work for every date:
datediff(day, dateadd(day, 1-day(@date), @date),
dateadd(month, 1, dateadd(day, 1-day(@date), @date)))
sha...