The Art of R Programming

Using Rprof() to Find Slow Spots in Your Code

If you think your R code is running unnecessarily slowly, a handy tool for finding the culprit is Rprof(), which gives you a report of (approximately) how much time your code is spending in each of the functions it calls. This is important, as it may not be wise to optimize every section of your program. Optimization may come at the expense of coding time and code clarity, so it’s of value to know where optimization would really help.

Monitoring with Rprof()

Let’s demonstrate using Rprof() with our three versions of code to find a powers matrix from the previous extended example. We’ll call Rprof() to get the monitor started, run our code, and then call Rprof() with a NULL argument to stop the monitoring. ...