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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
...ies, levels=c(levels(iris$Species), "empty_level"))
# Species is a factor and empty groups are included in the output
iris %>% group_by(Species, .drop=FALSE) %>% tally
#> Species n
#> 1 setosa 50
#> 2 versicolor 50
#> 3 virginica 50
#> 4 empty_level ...
Undefined reference to pthread_create in Linux
...h answers to this question so far are incorrect.
For Linux the correct command is:
gcc -pthread -o term term.c
In general, libraries should follow sources and objects on command line, and -lpthread is not an "option", it's a library specification. On a system with only libpthread.a installed,
g...
Converting Python dict to kwargs?
...want to build a query for sunburnt(solr interface) using class inheritance and therefore adding key - value pairs together. The sunburnt interface takes keyword arguments. How can I transform a dict ({'type':'Event'}) into keyword arguments (type='Event') ?
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Why are exclamation marks used in Ruby methods?
...oo # prints modified foo
This will output:
a string
In the standard libraries, there are a lot of places you'll see pairs of similarly named methods, one with the ! and one without. The ones without are called "safe methods", and they return a copy of the original with changes applied...
html5 localStorage error with Safari: “QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to
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Any particular reason you (and @KingKongFrog) are using window.sessionStorage to detect if you can write to localStorage or are we in a weird copy-paste typo cycle?
– Yetti
Apr 24 '14 at 21:09
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Using ThreadPool.QueueUserWorkItem in ASP.NET in a high traffic scenario
...read at all.
That goes for both free threads, created by new Thread(...), and worker threads in the ThreadPool that respond to QueueUserWorkItem requests.
Yes, it's true, you can starve the ThreadPool in an ASP.NET process by queuing too many work items. It will prevent ASP.NET from processing fu...
When should I use Arrow functions in ECMAScript 6?
...ght about code style in the context of the upcoming ECMAScript 6 (Harmony) and who have already worked with the language.
9...
When should a class be Comparable and/or Comparator?
I have seen classes which implement both Comparable and Comparator . What does this mean? Why would I use one over the other?
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Why git can't remember my passphrase under Windows
I have just start using git and i can't get it to remember my passphrase I'm using cmd.exe elevated and my git host is github and i have create a ssh key like that guide on github
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Disable building workspace process in Eclipse
... is running? Can i disable it because it is taking a long time to complete and i dont know if it is necessary. Thank you
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