[Rd] "Fastest" way to merge 300+ .5MB dataframes?
gcr at wisdomandwonder.com
Sun Aug 10 20:18:21 CEST 2014
Today I was working on a practice problem. It was simple, and perhaps
even realistic. It looked like this:
• Get a list of all the data files in a directory
• Load each file into a dataframe
• Merge them into a single data frame
Because all of the columns were the same, the simplest solution in my
mind was to `Reduce' the vector of dataframes with a call to
`merge'. That worked fine, I got what was expected. That is key
actually. It is literally a one-liner, and there will never be index
or scoping errors with it.
Now with that in mind, what is the idiomatic way? Do people usually do
something else because it is /faster/ (by some definition)?
Grant Rettke | ACM, ASA, FSF, IEEE, SIAM
gcr at wisdomandwonder.com | http://www.wisdomandwonder.com/
“Wisdom begins in wonder.” --Socrates
((λ (x) (x x)) (λ (x) (x x)))
“Life has become immeasurably better since I have been forced to stop
taking it seriously.” --Thompson
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