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Group by multiple columns in dplyr, using string vector input
...ike so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the columns we want to average within
columns = names(data)[-3]
library(dplyr)
df1 <- data...
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How to check if command line tools is installed
I have a macbook pro with OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is ...
Limit results in jQuery UI Autocomplete
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How to run a shell script at startup
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301
In the file you put in /etc/init.d/ you have to set it executable with:
chmod +x /etc/init.d/st...
How to know if two arrays have the same values
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function arraysEqual(_arr1, _arr2) {
if (!Array.isArray(_arr1) || ! Array.isArray(_arr2) || _arr1.length !== _arr2.length)
return false;
var arr1 = _arr1.concat().sort();
var arr2 = _arr2.concat().sort();
for (var i = 0; i &l...
Vim users, where do you rest your right hand? [closed]
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120
I think that jkl; is actually the more appropriate usage for vi. For one, h and l really don't...
Ninject vs Unity for DI [closed]
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answered Jun 28 '09 at 12:18
MendeltMendelt
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Search All Fields In All Tables For A Specific Value (Oracle)
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Is there a way to do repetitive tasks at intervals?
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edited Nov 13 '17 at 16:04
gsamaras
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