R, rbind with multiple files defined by a variable

Question

First off, this is related to a homework question for the Coursera R programming course. I have found other ways to do what I want to do but my research has led me to a question

Answer 1

A vector is not accepted for 'file' in read.csv(file, ...)

Below is a slight modification of yours. A vector of file paths are created and they are looped by sapply.

files <- paste("directory-name/",formatC(1:332, width=3, flag="0"),
               ".csv",sep="")
pollutantmean <- function(file, pollutant) {
    dataset <- read.csv(file, header = TRUE)
    mean(dataset[, pollutant], na.rm = TRUE)
}
sapply(files, pollutantmean)