deprecated/demo.R

In eddelbuettel/rbenchmark: Benchmarking routine for R

#!/usr/bin/env Rscript

# loading benchmark directly from googlecode
source('http://rbenchmark.googlecode.com/svn/trunk/benchmark.r')

# example 1
# benchmark the allocation of one 10^6-element numeric vector,
# replicated 100 times
result = benchmark(1:10^6)
print(result)

# example 2
# benchmark the application of two functions with like functionality but different implementation
means.rep = function(n, m) mean(replicate(n, rnorm(m)))
means.pat = function(n, m) colMeans(array(rnorm(n*m), c(m, n)))
result = benchmark(
   rep=means.rep(100, 100), 
   pat=means.pat(100, 100), 
   replications=10^(1:3),
   order=c('replications', 'elapsed'))
print(result)
   
# example 3
# six benchmarks for means.pat(100, 100), each with 100 replications
means.pat = function(n, m) colMeans(array(rnorm(n*m), c(m, n)))
result = within(
   benchmark(
      replications=rep(100, 3), 
      means.pat(100, 100), 
      means.pat(100, 100), 
      columns=c('test', 'elapsed', 'replications')),
   {average=elapsed/replications})
print(result)

# example 4
# application of benchmark to a list of arbitrary expressions
# calculate relative timings based on the user.self timings
means.rep = function(n, m) mean(replicate(n, rnorm(m)))
means.pat = function(n, m) colMeans(array(rnorm(n*m), c(m, n)))
tests = list(
   rep=expression(means.rep(100, 100)),
   pat=expression(means.pat(100, 100)))
result = do.call(benchmark, 
   c(tests, list(
      replications=100, 
      columns=c('test', 'user.self', 'replications', 'relative'), 
      order='elapsed',
      relative='user.self')))
print(result)