From gcr at wisdomandwonder.com  Sun Aug 10 20:49:33 2014
From: gcr at wisdomandwonder.com (Grant Rettke)
Date: Sun, 10 Aug 2014 13:49:33 -0500
Subject: [Rd] "Fastest" way to merge 300+ .5MB dataframes?
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My sincere apologies.

Having read http://www.r-project.org/posting-guide.html , I had wanted
to post this one to R-help.
Grant Rettke | ACM, ASA, FSF, IEEE, SIAM
gcr at wisdomandwonder.com | http://www.wisdomandwonder.com/
?Wisdom begins in wonder.? --Socrates
((? (x) (x x)) (? (x) (x x)))
?Life has become immeasurably better since I have been forced to stop
taking it seriously.? --Thompson


On Sun, Aug 10, 2014 at 1:28 PM, Joshua Ulrich <josh.m.ulrich at gmail.com> wrote:
> The same comment Jeroen Ooms made about your last email also applies
> to this one: it is better suited to R-help.
> --
> Joshua Ulrich  |  about.me/joshuaulrich
> FOSS Trading  |  www.fosstrading.com
>
>
> On Sun, Aug 10, 2014 at 1:18 PM, Grant Rettke <gcr at wisdomandwonder.com> wrote:
>> Good afternoon,
>>
>> 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)?
>>
>> Kind regards,
>>
>>
>> Grant Rettke | ACM, ASA, FSF, IEEE, SIAM
>> gcr at wisdomandwonder.com | http://www.wisdomandwonder.com/
>> ?Wisdom begins in wonder.? --Socrates
>> ((? (x) (x x)) (? (x) (x x)))
>> ?Life has become immeasurably better since I have been forced to stop
>> taking it seriously.? --Thompson
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel



[Rd] "Fastest" way to merge 300+ .5MB dataframes?
Grant Rettke