News about speeding R up
The most visited post ever on the ‘Og was In{s}a(ne), my report on Radford Neal’s experiments with speeding up R by using different brackets (the second most populat was Ross Ihaka’s comments, “simply start over and build something better”). I just spotted two new entries by Radford on his blog that are bound to rekindle the debate about the speed of R. The latest one shows that matrix multiplication can be made close to ten time faster by changing the way testing for the presence of NaN’s in a matrix is operated. This gain is not as shocking as producing a 25% improvement when replacing x=1/(1+x) with x=1/{1+x}, but a factor 10 is such a major gain…
June 5, 2012 at 7:47 pm
I love R, but maybe we should keep one eye on Julia:
http://julialang.org/
May 24, 2011 at 8:04 pm
Ok, 10 times is starting to get serious. However, did you know that data.table can have speed up factors of over 500 times? See the vignettes for reproducible examples and the data.table wiki for 5 other worked examples with speed up factors of 50, 170, 19, 230 and 92 times. The vignettes show data.table can be 35 times faster than tapply(). Those tests are just on 32bit, even larger speedups may be realised on 64bit examples.
http://datatable.r-forge.r-project.org/
http://rwiki.sciviews.org/doku.php?id=packages:cran:data.table
Matthew