# In{s}a(ne)!!

**Xi'an's Og » 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.

**H**aving missed the earliest entry by Radford last month, due to disconnection in Yosemite, I was stunned to read his three entries of the past month about R performances being significantly modify when changing brackets with curly brackets! I (obviously!) checked on my own machine and found indeed the changes in system.time uncovered by Radford… The worst is that I have a tendency to use redundant brackets to separate entities in long expressions and thus make them more readable (I know, this is debatable!), so each new parenthesis add to the wasted time… Note that it is the same with curly bracket: any extra curly bracket takes some additional computing time…

> f=function(n) for (i in 1:n) x=1/(1+x)

> g=function(n) for (i in 1:n) x=(1/(1+x))

> h=function(n) for (i in 1:n) x=(1+x)^(-1)

> j=function(n) for (i in 1:n) x={1/{1+x}}

> k=function(n) for (i in 1:n) x=1/{1+x}

> x=1

> system.time(f(10^6))

user system elapsed

1.684 0.020 1.705

> system.time(g(10^6))

user system elapsed

1.964 0.012 1.976

> system.time(h(10^6))

user system elapsed

2.452 0.016 2.470

> system.time(j(10^6))

user system elapsed

1.716 0.008 1.725

> system.time(k(10^6))

user system elapsed

1.532 0.016 1.548

**I**n the latest of his posts, Radford lists a series of 14 patches that speed up R up to 25%… That R can face such absurdities is pretty annoying! Given that I am currently fighting testing an ABC algorithm with MCMC inner runs, which takes forever to run, this is even depressing!!! As Radford stresses, “slow speed is a significant impediment to greater use of R, much more so than lack of some wish list of new features.”

Filed under: R, Statistics Tagged: brackets, R, Radford Neal, speed, system.time

**leave a comment**for the author, please follow the link and comment on their blog:

**Xi'an's Og » 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.