How skip some line in R

February 13, 2022

I have many URLs which I import their text in R.
I use this code:

setNames(lapply(1:1000, function(x) gettxt(get(paste0("url", x)))), paste0("url", 1:1000, "_txt")) %>% 
  list2env(envir = globalenv())

However, some URLs can not import and show this error:

Error in file(con, "r") : cannot open the connection In addition:
Warning message: In file(con, "r") : InternetOpenUrl failed: ‘A
connection with the server could not be established’

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So, my code doesn’t run and doesn’t import any text from any URL.
How can I recognize wrong URLs and skip them in other to import correct URLs?

>Solution :

one possible aproach besides trycatch mentioned by @tester can be the purrr-package:

library(purrr)
# declare function
my_gettxt <- function(x) {
    gettxt(get(paste0("url", x)))
}
# make function error prone by defining the otherwise value (could be empty df with column defintion, etc.) used as output if function fails
my_gettxt <- purrr::possibly(my_gettxt , otherwise = NA)
# use map from purrr instead of apply function
my_data <- purrr::map(1:1000, ~my_gettxt(.x))