How to split a number into its digits in R

Question

new here so forgive me if this sounds dumb.

I am currently working on a project, the data set has a variable that consists of two digits. For example 12 or 34. The second digit is from 1 to 5 and I need to isolate this one. There are round about 18 000 observations so doing this manually is not an option for me.

I tried the seperate function from dplyr.

demog %>% separate(socioEcon, c("A", "B"))

I also tried a couple of other things which I already deleted.

How would you guys try to split the data?

please post a [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) — Eric, Jun 24 '22 at 19:03
What about: `demog %>% separate(socioEcon, c("A", "B"), sep = "")`? — PaulS, Jun 24 '22 at 19:03

score 3 · Answer 1 · answered Jun 24 '22 at 19:04

3

demog %>% mutate(B = socioEcon %% 10)

answered Jun 24 '22 at 19:04

Dmitry Zotikov

2,133
15
12

score 0 · Answer 2 · answered Jun 24 '22 at 19:19

Most separation options ask you to make it a character, so you just need to convert data types back and forth. Here's a riff of my answer here: using strsplit and subset in dplyr and mutate

library(tidyverse)

tribble(
  ~id, ~to_split,
  1, 15,
  2, 42,
  3, 53
) %>% 
  dplyr::mutate(second_digit = stringr::str_split(as.character(to_split), "") %>% 
                  purrr::map_chr(., 2))

As you can see, we're using str_split on a character vector and splitting by nothing (so you get each character), then using purrr's mapping to grab the second character. This is more efficient at a larger scale than dplyr's separate but you could also use that once it's converted to a character vector.

However, the most efficient way is definitely to do the math as your other answer provided. :)

score 0 · Accepted Answer · answered Jun 24 '22 at 19:20

0

demog <- data.frame(socioEcon = c(12,34))

library(dplyr)
demog %>%
  mutate(socioEcon = as.character(socioEcon)) %>%
  tidyr::separate(socioEcon, c("A", "B"), sep = 1, remove = F)


  socioEcon A B
1        12 1 2
2        34 3 4

answered Jun 24 '22 at 19:20

Jon Spring

55,165
4
35
53

score 0 · Answer 4 · answered Jun 24 '22 at 23:24

0

demog <- data.frame(socioEcon = c(12,34))

library(stringr)
demog[, c("A", "B")] <- as.numeric(str_split_fixed(demog$socioEcon, "", 2))

answered Jun 24 '22 at 23:24

carl

305
2
13

How to split a number into its digits in R

4 Answers4