I try to think there is any way I can have multiple variables for each argument. If I used ensyms, I can't have a vector like I provided in function, but I would love to have the function works for both way groups = c(am, vs) or groups = c("am", "vs")
The first 2 giving me 2 more columns if I used groups = c("am", "vs"), the last two are working correctly if I used groups = c(am, vs). The selected_var is working correctly either I used select_vars = c( "mpg","disp") or select_vars = c( mpg, disp)
Any idea will help?
tryfn <- function(data, select_vars,groups, ...){
select_vars <- as.list(rlang::enexpr(select_vars ))
select_vars <- if(length(select_vars) > 1) select_vars[-1] else select_vars
group_vars <- as.list(rlang::enexpr(groups))
group_vars <- if(length(group_vars ) > 1) group_vars[-1] else group_vars
data %>% select(!!!group_vars,!!!select_vars) %>% group_by(!!!group_vars)
}
# If I used groups argument as string, it gave me 2 extra columns
tryfn(mtcars, select_vars = c( "mpg","disp"), groups = c("am", "vs"))
tryfn(mtcars, select_vars = c( mpg, disp), groups = c("am", "vs"))
> tryfn(mtcars, select_vars = c( mpg, disp), groups = c("am", "vs"))
# A tibble: 32 x 6
# Groups: "am", "vs" [1]
am vs mpg disp **`"am"` `"vs"`**
<dbl> <dbl> <dbl> <dbl> <chr> <chr>
1 1 0 21 160 am vs
2 1 0 21 160 am vs
3 1 1 22.8 108 am vs
4 0 1 21.4 258 am vs
5 0 0 18.7 360 am vs
6 0 1 18.1 225 am vs
7 0 0 14.3 360 am vs
8 0 1 24.4 147. am vs
9 0 1 22.8 141. am vs
10 0 1 19.2 168. am vs
# this one is working perfectly
tryfn(mtcars, select_vars = c( mpg, disp), groups = c(am, vs))
tryfn(mtcars, select_vars = c( "mpg","disp"), groups = c(am, vs))
> tryfn(mtcars, select_vars = c( "mpg","disp"), groups = c(am, vs))
# A tibble: 32 x 4
# Groups: am, vs [4]
am vs mpg disp
* <dbl> <dbl> <dbl> <dbl>
1 1 0 21 160
2 1 0 21 160
3 1 1 22.8 108
4 0 1 21.4 258
5 0 0 18.7 360
6 0 1 18.1 225
7 0 0 14.3 360
8 0 1 24.4 147.
9 0 1 22.8 141.
10 0 1 19.2 168.
I add one line group_vars <- purrr::map(group_vars, as.symbol) to your function. This makes sure that the items in group_vars will turn into symbols.
tryfn <- function(data, select_vars,groups, ...){
select_vars <- as.list(rlang::enexpr(select_vars))
select_vars <- if(length(select_vars) > 1) select_vars[-1] else select_vars
group_vars <- as.list(rlang::enexpr(groups))
group_vars <- if(length(group_vars ) > 1) group_vars[-1] else group_vars
group_vars <- purrr::map(group_vars, as.symbol)
data %>% select(!!!group_vars,!!!select_vars) %>% group_by(!!!group_vars)
}