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Group by multiple columns in dplyr, using string vector input
...oup_by_at(vars(one_of(columns))) %>%
summarize(Value = mean(value))
#compare plyr for reference
df2 <- plyr::ddply(data, columns, plyr::summarize, value=mean(value))
table(df1 == df2, useNA = 'ifany')
## TRUE
## 27
The output from your example question is as expected (see comparison to...
Edit and Continue: “Changes are not allowed when…”
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community wiki
5 revs, 2 users 71%nightcoder
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adb server version doesn't match this client
... your adb by going into folder platform-tools which adb placed and do this command:
./adb kill-server
./adb start-server
*tips: You may close the process of Genymotion before running the command above
Hope this help.
sh...
How to check if element in groovy array/hash/collection/list?
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Petter Friberg
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answered Oct 8 '16 at 16:41
HinataXVHinataXV
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Javascript checkbox onChange
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EugeneEugene
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How to encode the filename parameter of Content-Disposition header in HTTP?
...re is discussion of this, including links to browser testing and backwards compatibility, in the proposed RFC 5987, "Character Set and Language Encoding for Hypertext Transfer Protocol (HTTP) Header Field Parameters."
RFC 2183 indicates that such headers should be encoded according to RFC 2184, whi...
PUT vs. POST in REST
...pdate a resource
POST /questions/<existing_question> HTTP/1.1
Host: www.example.com/
Note that the following is an error:
POST /questions/<new_question> HTTP/1.1
Host: www.example.com/
If the URL is not yet created, you
should not be using POST to create it
while specif...
How do I include a pipe | in my linux find -exec command?
... -printf "zcat %p | agrep -dEOE 'grep'\n" | sh
This constructs a list of commands using pipes to execute, then sends these to a new shell to actually be executed. (Omitting the final "| sh" is a nice way to debug or perform dry runs of command lines like this.)
In terms of efficiency this result...