B Dittmann
2015-Apr-10 20:20 UTC
[R] multiple input files single output - lapply? - pls advise
Dear R users, hope you can point me in the right direction. I am stuck with the following problem. My function "f1" reads csv files, manipulates them into the right xts format and returns the output at the end. This works perfectly fine. Now, I need to run "f1" over a long list of various csv files, all of the same format, but different dates (or time stamps) which is guaranteed by design. All these individual results per each file I hope to combine into one xts or zoo object. I tried "lapply" as follows: # all csv files start with "z1": file.names <- list.files(pattern = "z1*", full.names = T, recursive = FALSE) # my function: f1 <- function(x, param){ # x: the csv file # param: some parameter for calculation # spits results out return(results) } res <- lapply(file.names, function(x){f1(x, param)}) I wrote the output to "res" and by subsetting res[1], res[2], ... I can retrieve the results of each individual csv file on which I applied my function "f1". How could I append or merge all individual results res[i] for my i csv files into one xts or zoo object? Many thanks in advance, Bernard [[alternative HTML version deleted]]