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dplyr: “Error in n(): function should not be called directly”
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Michael Bellhouse
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answered Apr 2 '14 at 3:59
mnelmnel
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Which is the fastest algorithm to find prime numbers?
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mmcdole
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answered Jan 17 '09 at 18:45
Greg Hewgil...
How to install 2 Anacondas (Python 2 and 3) on Mac OS
...ust installed XCode (for c++ compiler) and Anaconda with the latest Python 3 (for myself). Now I'm wondering how to install properly second Anaconda (for work) with Python 2?
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How can I draw vertical text with CSS cross-browser?
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213
Updated this answer with recent information (from CSS Tricks). Kudos to Matt and Douglas for poi...
In Python, how do I iterate over a dictionary in sorted key order?
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173
Haven't tested this very extensively, but works in Python 2.5.2.
>>> d = {"x":2, "h":1...
File path to resource in our war/WEB-INF folder?
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3 Answers
3
Active
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Is MonoTouch now banned on the iPhone? [closed]
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answered Apr 8 '10 at 23:11
Lance McNearneyLance McNearney
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Python: List vs Dict for look up table
...M. Kuchling in Beautiful Code, the implementation tries to keep the hash 2/3 full, so you might waste quite some memory.
If you do not add new entries on the fly (which you do, based on your updated question), it might be worthwhile to sort the list and use binary search. This is O(log n), and is ...
R - Concatenate two dataframes?
...olumn b to data frame b.
Results
> a <- data.frame(a=c(0,1,2), b=c(3,4,5), c=c(6,7,8))
> a
a b c
1 0 3 6
2 1 4 7
3 2 5 8
> b <- data.frame(a=c(9,10,11), c=c(12,13,14))
> b
a c
1 9 12
2 10 13
3 11 14
> b$b <- NA
> b
a c b
1 9 12 NA
2 10 13 NA
3 11 14 NA
> ...