Splitting a Long String into smaller strings

Question

I have a dataframe that includes a column of numbers like this:

360010001001002
360010001001004
360010001001005
360010001001006

I'd like to break into chunks of 2 digits, 3 digits, 5 digits, 1 digit, 4 digits:

36 001 00010 0 1002
36 001 00010 0 1004
36 001 00010 0 1005
36 001 00010 0 1006

That seems like it should be straightforward but I'm reading the strsplit documentation and I can't sort out how I'd do this by lengths.

Answer 1

You can use substring (assuming the length of string/number is fixed):

xx <- c(360010001001002, 360010001001004, 360010001001005, 360010001001006)
out <- do.call(rbind, lapply(xx, function(x) as.numeric(substring(x, 
                     c(1,3,6,11,12), c(2,5,10,11,15)))))
out <- as.data.frame(out)

Answer 2

Assuming this data:

x <- c("360010001001002", "360010001001004", "360010001001005", "360010001001006")

try this:

read.fwf(textConnection(x), widths = c(2, 3, 5, 1, 4))

If x is numeric then replace x with as.character(x) in this statement.

Answer 3

A functional version:

split.fixed.len <- function(x, lengths) {
   cum.len <- c(0, cumsum(lengths))
   start   <- head(cum.len, -1) + 1
   stop    <- tail(cum.len, -1)
   mapply(substring, list(x), start, stop)
}    

a <- c(360010001001002,
       360010001001004,
       360010001001005,
       360010001001006)

split.fixed.len(a, c(2, 3, 5, 1, 4))
#      [,1] [,2]  [,3]    [,4] [,5]  
# [1,] "36" "001" "00010" "0"  "1002"
# [2,] "36" "001" "00010" "0"  "1004"
# [3,] "36" "001" "00010" "0"  "1005"
# [4,] "36" "001" "00010" "0"  "1006"