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How to sum a variable by group
...Frequency, by=list(Category=x$Category), FUN=sum)
Category x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same data type can be incorporated via cbind:
aggregate(cbind(x$Frequency, x$Metri...
How to pass all arguments passed to my bash script to a function of mine? [duplicate]
...ter expands to a separate word. That is "$@" is equivalent to "$1" "$2" "$3"....
Passing some arguments:
If you want to pass all but the first arguments, you can first use shift to "consume" the first argument and then pass "$@" to pass the remaining arguments to another command. In bash (and zsh ...
Python JSON serialize a Decimal object
I have a Decimal('3.9') as part of an object, and wish to encode this to a JSON string which should look like {'x': 3.9} . I don't care about precision on the client side, so a float is fine.
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Why can't I use a list as a dict key in python?
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There's a good article on the topic in the Python wiki: Why Lists Can't Be Dictionary Keys. As ...
How to add multiple files to Git at the same time
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answered Oct 24 '13 at 20:39
daxdax
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Removing the first 3 characters from a string [closed]
What is the most efficient way to remove the first 3 characters of a string?
3 Answers
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How do I combine two data-frames based on two columns? [duplicate]
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3 Answers
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