Code optimization, an Rcpp solution
[This article was first published on Romain Francois, Professional R Enthusiast - Tag - R, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.
Tony Breyal woke up an old code optimization problem in this blog post, so I figured it was time for an Rcpp based solution
This solutions moves down Henrik Bengtsson’s idea (which was at the basis of attempt 10) down to C++. The idea was to call sprintf less than the other solutions to generate the strings “001”, “002”, “003”, …
We can benchmark this version using the rbenchmark package:
> library(rbenchmark)
> n <- 2000
> benchmark(
+ generateIndex10(n),
+ generateIndex11(n),
+ generateIndex12(n),
+ generateIndex13(n),
+ generateIndex14(n),
+ columns =
+ c("test", "replications", "elapsed", "relative"),
+ order = "relative",
+ replications = 20
+ )
test replications elapsed relative
5 generateIndex14(n) 20 21.015 1.000000
3 generateIndex12(n) 20 22.034 1.048489
4 generateIndex13(n) 20 23.436 1.115203
2 generateIndex11(n) 20 23.829 1.133904
1 generateIndex10(n) 20 30.580 1.455151
>
To leave a comment for the author, please follow the link and comment on their blog: Romain Francois, Professional R Enthusiast - Tag - R.
R-bloggers.com offers daily e-mail updates about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job.
Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.