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How does one reorder columns in a data frame?
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354
Your dataframe has four columns like so df[,c(1,2,3,4)].
Note the first comma means keep all t...
How I can delete in VIM all text from current line to end of file?
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370
dG will delete from the current line to the end of file
dCtrl+End will delete from the cursor...
Python's “in” set operator
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13
If someone implemented his class's hash function in a twisted way, this is what he may get (and deserve).
– ugoren
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How to create a tuple with only one element
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3 Answers
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Can I use `pip` instead of `easy_install` for `python setup.py install` dependency resolution?
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3 Answers
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Dynamically select data frame columns using $ and a character value
... 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. Sec...
Get specific ArrayList item
How can I get a specific item from this ArrayList ? mainList[3] ?
8 Answers
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