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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...
How to upgrade PowerShell version from 2.0 to 3.0
...w.microsoft.com/en-us/download/details.aspx?id=34595. You need Windows 7 SP1 though.
It's worth keeping in mind that PowerShell 3 on Windows 7 does not have all the cmdlets as PowerShell 3 on Windows 8. So you may still encounter cmdlets that are not present on your system.
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Are the shift operators () arithmetic or logical in C?
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Compiling and running a Java application on Mac OSX, or any major operating system, is very ea...
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Error message Strict standards: Non-static method should not be called statically in php
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Your methods are missing the static keyword. Change
function getInstanceByName($name=''){
t...
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Call getCurrentFocus() on the Activity.
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Getting root permissions on a file inside of vi? [closed]
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Can I specify a custom location to “search for views” in ASP.NET MVC?
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