I have a vector here and each element is composed of a double-digit. I put it into a data frame. But is there any smart way to break down the elements? For example how to make two extra columns based on the number in the vector? 23 2 3 like this!
combination <- c(11, 12, 13, 14, 15, 16, 23, 24, 25, 26, 34, 35, 36, 45, 46, 56) # How to do it smartly?
crop.combinations <- rep(combination, each=num.rep)
Assuming you only have 2-digits numbers you can use some elementary math operations:
df = data.frame(
x = c(11, 12, 13, 14, 15, 16, 23, 24, 25, 26, 34, 35, 36, 45, 46, 56)
)
df$x1 = df$x %/% 10
df$x2 = df$x %% 10
# x x1 x2
# 1 11 1 1
# 2 12 1 2
# 3 13 1 3
# 4 14 1 4
# 5 15 1 5
# 6 16 1 6
# 7 23 2 3
# 8 24 2 4
# 9 25 2 5
# 10 26 2 6
# 11 34 3 4
# 12 35 3 5
# 13 36 3 6
# 14 45 4 5
# 15 46 4 6
# 16 56 5 6
You can use tidyr::separate:
library(tidyr)
dat <- data.frame(combination = c(11, 12, 13, 14, 15, 16, 23, 24, 25, 26, 34, 35, 36, 45, 46, 56))
separate(dat, combination,
into = str_c("digit", seq(max(nchar(combination)))),
sep = "(?<=[0-9])",
remove = FALSE)
output
combination digit1 digit2
1 11 1 1
2 12 1 2
3 13 1 3
4 14 1 4
5 15 1 5
6 16 1 6
7 23 2 3
8 24 2 4
9 25 2 5
10 26 2 6
11 34 3 4
12 35 3 5
13 36 3 6
14 45 4 5
15 46 4 6
16 56 5 6
Or, with base R's strsplit:
as.data.frame(do.call(rbind, strsplit(as.character(combination), "")))
You can use extract:
library(tidyr)
data.frame(combination) %>%
extract(combination,
into = c("1st", "2nd"),
regex = "(.)(.)",
remove = FALSE)
combination 1st 2nd
1 11 1 1
2 12 1 2
3 13 1 3
4 14 1 4
5 15 1 5
6 16 1 6
7 23 2 3
8 24 2 4
9 25 2 5
10 26 2 6
11 34 3 4
12 35 3 5
13 36 3 6
14 45 4 5
15 46 4 6
16 56 5 6
If you add convert = TRUE, the new columns will be converted to numeric.
substr() is another (simple) option.
> combination <- c(11, 12, 13, 14, 15, 16, 23, 24, 25, 26, 34, 35, 36, 45, 46, 56)
> substr(combination, 1, 1)
[1] "1" "1" "1" "1" "1" "1" "2" "2" "2" "2" "3" "3" "3" "4" "4" "5"
> substr(combination, 2, 2)
[1] "1" "2" "3" "4" "5" "6" "3" "4" "5" "6" "4" "5" "6" "5" "6" "6"