[R] R package "benchmark"

Benchmark package consists of only one function benchmark, which is a simple wrapper of system.time to evaluate expression of R code.

Usage:

benchmark(...,columns = c("test", "replications", "elapsed", "relative", "user.self", "sys.self",
"user.child", "sys.child"), order = "test", replications = 100, environment = parent.frame(), relative = "elapsed")

It means evaluate expression $...$ and return the results of c("test", "replications", "elapsed", "relative", "user.self", "sys.self",
"user.child", "sys.child"). All column result can be choose which to return using column setting.

Now give the meaning of each column:

• test means expression (R code) to be evaluated.
• replications means the number of replications used within each individual benchmark.
• elapsed means the total elapsed times for the currently running R process
• user.self means ‘user.time’, which is the CPU time charged for the execution of user instructions of the calling process.
• sys.selt mean ‘system.time’, which is the CPU time charged for execution by the system on behalf of the calling process.
• user.child and sys.child are not available on Windows and will always be given as NA.
• relative means the relative value or time using of the evaluated expressions.

So the we can use elapsed time to compare R processes, which can be seen relative directly.

From the blog,
the result of benchmark is

From the column relative, we see that

• rbindlist is the fastest way