On Oct 27, 2012, at 01:34 , sffarooqi wrote: > Hi all, > I have a very quick question on how to use the summation sign in R for the > function. > HereĀ“s a basic example: the function is sum(i=1 to 5)log(1-xi^2) > Id be grateful if someone knows how to do this without writing it out 5 > times - I am looking sth along the lines of the following: > > computeR <- function(x) > { > return (-sum(log(1-x^2)) > }^ > thank you vm in advance!
You pretty much did it already: > x <- c(.5,.6,.7,.4,.8) > -sum(log(1-x^2)) [1] 2.603318 I.e., just have x as a vector of length 5 and the rest is done automagically. (And, BTW, you don't need return() in a function like that in R, the return value is the value of the last expression.) -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.