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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...
Convert HashBytes to VarChar
I want to get the MD5 Hash of a string value in SQL Server 2005. I do this with the following command:
7 Answers
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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 to put spacing between TBODY elements
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12 Answers
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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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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 algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
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2
I had a hard time trying to imagine how optimal this could work. So I've coded it (with a square shape) and the results are great. Here's a ...
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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