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Grouping functions (tapply, by, aggregate) and the *apply family
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Why does [5,6,8,7][1,2] = 8 in JavaScript?
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[1,2,3,4,5,6][1,2,3];
^ ^
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array + — array subscript access operation,
where index is `1,2,3`,
which is an expression that evaluates to `3`.
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Why doesn't Python have a sign function?
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How to use if - else structure in a batch file?
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Your syntax is incorrect. You can't use ELSE IF. It appears that you don't really need it anyw...
Center a map in d3 given a geoJSON object
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Are list-comprehensions and functional functions faster than “for loops”?
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The following are rough guidelines and educated guesses based on experience. You should timeit...
Summarizing multiple columns with dplyr? [duplicate]
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#> <int> <dbl> <dbl> <dbl> <dbl>
#> 1 1 3.08 2.98 2.98 2.91
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrl...
Are there any O(1/n) algorithms?
Are there any O(1/n) algorithms?
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Getting Java version at runtime
I need to work around a Java bug in JDK 1.5 which was fixed in 1.6. I'm using the following condition:
12 Answers
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Big O, how do you calculate/approximate it?
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I'll do my best to explain it here on simple terms, but be warned that this topic takes my st...