x^(1/n) # ? exp(log(x)/n) # ? Either of those could be rolled into a function with the desired name: On Mar 19, 2009, at 11:21 AM, Martin Biuw wrote: > Hi, > Is there a function in R to calculate the nth root, similar to the > MATLAB function NTHROOT()? > Thanks, > Martin Biuw David Winsemius, MD Heritage Laboratories West Hartford, CT