Efficient alternatives to merge for larger data.frames R

Posted by Etienne Low-Décarie on Stack Overflow See other posts from Stack Overflow or by Etienne Low-Décarie
Published on 2012-06-21T21:22:58Z Indexed on 2012/06/22 9:16 UTC
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Filed under:

r

|

merge

|

data.frame

|

plyr

|

data.table

I am looking for an efficient (both computer resource wise and learning/implementation wise) method to merge two larger (size>1 million / 300 KB RData file) data frames.

"merge" in base R and "join" in plyr appear to use up all my memory effectively crashing my system.

Example
load test data frame

and try

test.merged<-merge(test, test)

or

test.merged<-join(test, test, type="all")

-

The following post provides a list of merge and alternatives:
How to join data frames in R (inner, outer, left, right)?

The following allows object size inspection:
https://heuristically.wordpress.com/2010/01/04/r-memory-usage-statistics-variable/

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Developer IT

Efficient alternatives to merge for larger data.frames R - Developer IT

Efficient alternatives to merge for larger data.frames R

r

merge

data.frame

plyr

data.table

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