I would like to reorder some columns to come after a particular other column using dplyr::relocate. Here is a MWE:
a <- letters[1:3]
b <- letters[4:6]
c <- letters[7:9]
d <- letters[10:12]
mytib <- tibble::tibble(a,b,c,d)
# A tibble: 3 x 4
# a b c d
# <chr> <chr> <chr> <chr>
# 1 a d g j
# 2 b e h k
# 3 c f i l
mytib %>%
relocate(c, .after = a)
This example works but is there a way that I could, with one relocate command, move c after a and, say, d after b?
I tried the following without success:
mytib %>%
relocate(c(c, d), .after(c(a, b)))
Edit 1: I explicitly ask about relocate because functions like select do not work for large datasets where all I know is after which column (name) I want to insert a column.
Edit 2: This is my expected output:
# A tibble: 3 x 4
# a c b d
# <chr> <chr> <chr> <chr>
# 1 a g d j
# 2 b h e k
# 3 c i f l
As dplyr::relocate itself apparently doesn't allow relocating in pairs, you can "hack" this behavior by preparing a list of column pairs like the ones you describe ("c after a" & "d after b") and reduce over that list, passing your df in as an .init value and in each reduce-step relocating one pair.
Like this:
library(dplyr)
library(purrr)
df_relocated <- reduce(
.x = list(c('c','a'), c('d','b')),
.f = ~ relocate(.x, .y[1], .after = .y[2]),
.init = mytib
)
This produces a tibble just as you expect it:
> df_relocated
# A tibble: 3 x 4
a c b d
<chr> <chr> <chr> <chr>
1 a g d j
2 b h e k
3 c i f l