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Dynamically select data frame columns using $ and a character value
...s a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Se...
What's the right OAuth 2.0 flow for a mobile app
...implement delegated authorization in a Web API for mobile apps using OAuth 2.0. According to specification, the implicit grant flow does not support refresh tokens, which means once an access token is granted for an specific period of time, the user must grant permissions to the app again once the t...
no acceptable C compiler found in $PATH when installing python
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edited Jun 13 '18 at 11:52
Duncan
26122 silver badges1717 bronze badges
answered Nov 6 '13 at 15:54
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Unix command to find lines common in two files
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220
The command you are seeking is comm. eg:-
comm -12 1.sorted.txt 2.sorted.txt
Here:
-1 : su...
How can I do DNS lookups in Python, including referring to /etc/hosts?
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edited Mar 7 '19 at 22:59
Justin M. Keyes
5,57011 gold badge2727 silver badges5656 bronze badges
a...
How to put spacing between TBODY elements
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12 Answers
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How to install therubyracer gem on 10.10 Yosemite?
...xec rake clean build binary
gem install pkg/libv8-3.16.14.3-x86_64-darwin-12.gem #note that libv8 version may change, so tab through files in pkg/, also remember to use the one with version specified
then just bundle your project gems
this is the only way it worked for me on 10.10 (ruby 2.1.2)
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Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
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126
Short of closing and reopening your tty (i.e. logging off and back on, which may also terminate...
What characters are allowed in DOM IDs? [duplicate]
..._" | [a-z] | [#xC0-#xD6] |
[#xD8-#xF6] | [#xF8-#x2FF] |
[#x370-#x37D] | [#x37F-#x1FFF] |
[#x200C-#x200D] | [#x2070-#x218F] |
[#x2C00-#x2FEF] | [#x3001-#xD7FF] |
[#xF900-#...
Rank function in MySQL
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270
One option is to use a ranking variable, such as the following:
SELECT first_name,
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