Thanks,Hans! I agree that this is a good way of solving this problem.
Here is another way. Instead of defining a vector of uni-dimensional functions and trying to integrating each component (a uni-dimensional function), we can do something below my.integrand<-function(x,k) { return(f[x,k]) ## use matrix to represent the sequence of uni-dimensional functions } my.integral<-function(k) ## k=1,...,5000 denotes the function labels { return(integrate(my.integrand,lower=...,upper=...,k)$value) } When calculating the integrals, just perform sapply(1:5000, my.integral) This is a way of avoiding loops but the computing time needs to be carefully examined. Jeff -- View this message in context: http://r.789695.n4.nabble.com/efficiently-finding-the-integrals-of-a-sequence-of-functions-tp4179452p4183323.html Sent from the R help mailing list archive at Nabble.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.