I have two lists that are the result of a for loop:

pid list <- List of IDs

violations <- List of Violations

Now, when I run the following:

df <- cbind(pid_list, violations) %>%
    as.data.frame()
head(df)

I end up with a dataframe with a column on the left and a list in the right that looks like this: Current Result

What I would like the result to be is:

So I can join it back to a previous table that I have and remove the rows with NULL violations.

I've tried some unlist() and purrr() methods without much success -- does anyone here have any recommendations?

CodePudding user response：

We could loop over the violations list, if the upper element is NULL, convert it to NA, extract the upper element, construct the data.frame by replicating the 'pid_list' based on the lengths of the violations list in base R

violations <- lapply(violations, \(x) {if(is.null(x$upper) || 
    length(x$upper) == 0) {x$upper <- NA}
        x$upper})
pid_list[lengths(pid_list) == 0| is.null(pid_list)] <- NA
data.frame(pid_list = unlist(pid_list)[rep(seq_along(pid_list), 
      lengths(violations))], 
     violations = unlist(violations))

-output

               pid_list violations
1  -6928390558574835712         NA
2  -6141623232242576384         NA
3  -4584655687749366272         NA
4  -2856811727809710592        381
5  -2856811727809710592        382
6  -2856811727809710592        383
7  -2856811727809710592        384
8  -2856811727809710592        385
9  -2856811727809710592        386
10 -2856811727809710592        387
11 -2856811727809710592        388
12 -1860498996583344128         NA
13  1345936609258173440         NA

data

violations <-  list(list(upper = integer(0)), list(upper = integer(0)), list( upper = integer(0)), list(upper = 381:388), list(upper = integer(0)), list(upper = integer(0))) 
pid_list <- list("-6928390558574835712", "-6141623232242576384", "-4584655687749366272", "-2856811727809710592", "-1860498996583344128", "1345936609258173440")