Define Variable based on other

[ramgouveia]

I have this dataframe

and I want this result

For each group I want to fill from day 1 to day 6.

Which is the code?

[FJCC]

Here are two methods.

#Methoc 1. Every Group has 6 members
DF <- data.frame(Group = rep(c("A","B","C","D"), each = 6),
                 Day = NA)
DF
#>    Group Day
#> 1      A  NA
#> 2      A  NA
#> 3      A  NA
#> 4      A  NA
#> 5      A  NA
#> 6      A  NA
#> 7      B  NA
#> 8      B  NA
#> 9      B  NA
#> 10     B  NA
#> 11     B  NA
#> 12     B  NA
#> 13     C  NA
#> 14     C  NA
#> 15     C  NA
#> 16     C  NA
#> 17     C  NA
#> 18     C  NA
#> 19     D  NA
#> 20     D  NA
#> 21     D  NA
#> 22     D  NA
#> 23     D  NA
#> 24     D  NA
DF$Day <- rep(1:6, times = 4)
DF
#>    Group Day
#> 1      A   1
#> 2      A   2
#> 3      A   3
#> 4      A   4
#> 5      A   5
#> 6      A   6
#> 7      B   1
#> 8      B   2
#> 9      B   3
#> 10     B   4
#> 11     B   5
#> 12     B   6
#> 13     C   1
#> 14     C   2
#> 15     C   3
#> 16     C   4
#> 17     C   5
#> 18     C   6
#> 19     D   1
#> 20     D   2
#> 21     D   3
#> 22     D   4
#> 23     D   5
#> 24     D   6

#Method 2, Groups do not have to have the same number of members
library(dplyr)
DF <- data.frame(Group = rep(c("A","B","C","D"), each = 6),
                 Day = NA)
DF <- DF |> group_by(Group) |> mutate(Day = row_number())
DF
#> # A tibble: 24 × 2
#> # Groups:   Group [4]
#>    Group   Day
#>    <chr> <int>
#>  1 A         1
#>  2 A         2
#>  3 A         3
#>  4 A         4
#>  5 A         5
#>  6 A         6
#>  7 B         1
#>  8 B         2
#>  9 B         3
#> 10 B         4
#> # … with 14 more rows

^{Created on 2023-03-23 with reprex v2.0.2}

[ramgouveia]

Thank you very much @FJCC

[peernisse]

Here is an approach that leaves the groups and number of times to repeat them flexible:

library(dplyr)

grps <- c('A','B','C','D')
reps <- 6


DF <- data.frame(
    Group = rep(grps, reps) %>% sort(.)
) %>% 
group_by(Group) %>% 
mutate(
    Day = seq(1:reps)
) %>% 
ungroup(.)

[ramgouveia]

Thank you very much @peernisse