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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...
Windows batch: call more than one command in a FOR loop?
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edited Jan 21 '14 at 10:08
Steven
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Restore file from old commit in git
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228
git checkout 'master@{7 days ago}' -- path/to/file.txt
This will not alter HEAD, it will jus...
WPF datagrid empty row at bottom
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answered Nov 23 '09 at 18:44
Tomi JunnilaTomi Junnila
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What does the “expand” option do in grunt-contrib-copy? The examples all use it but the docs say not
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2 Answers
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Active
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Adding and removing style attribute from div with jquery
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248
You could do any of the following
Set each style property individually:
$("#voltaic_holder")...
How does one use rescue in Ruby without the begin and end block
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226
A method "def" can serve as a "begin" statement:
def foo
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rescue
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end
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When should i use npm with “-g” flag and why?
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2 Answers
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When should I use std::thread::detach?
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answered Apr 2 '14 at 7:50
Matthieu M.Matthieu M.
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How do I append text to a file?
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125
cat >> filename
This is text, perhaps pasted in from some other source.
Or else entered a...