Is there a way to use pmax and pmin function in R with a vector of string variable names using the tidyverse (dplyr) format?
For instance, I want to run the following:
data(mtcars)
mtcars %>% mutate(maxval = pmax(drat, wt, na.rm = T)
This properly gets me the following:
mpg cyl disp hp drat wt qsec vs am gear carb maxval
Mazda RX4 21.0 6 160.0 110 3.90 2.620 16.46 0 1 4 4 3.900
Mazda RX4 Wag 21.0 6 160.0 110 3.90 2.875 17.02 0 1 4 4 3.900
Datsun 710 22.8 4 108.0 93 3.85 2.320 18.61 1 1 4 1 3.850
Hornet 4 Drive 21.4 6 258.0 110 3.08 3.215 19.44 1 0 3 1 3.215
Hornet Sportabout 18.7 8 360.0 175 3.15 3.440 17.02 0 0 3 2 3.440
Valiant 18.1 6 225.0 105 2.76 3.460 20.22 1 0 3 1 3.460
Duster 360 14.3 8 360.0 245 3.21 3.570 15.84 0 0 3 4 3.570
Merc 240D 24.4 4 146.7 62 3.69 3.190 20.00 1 0 4 2 3.690
Merc 230 22.8 4 140.8 95 3.92 3.150 22.90 1 0 4 2 3.920
Merc 280 19.2 6 167.6 123 3.92 3.440 18.30 1 0 4 4 3.920
Merc 280C 17.8 6 167.6 123 3.92 3.440 18.90 1 0 4 4 3.920
Merc 450SE 16.4 8 275.8 180 3.07 4.070 17.40 0 0 3 3 4.070
Merc 450SL 17.3 8 275.8 180 3.07 3.730 17.60 0 0 3 3 3.730
Merc 450SLC 15.2 8 275.8 180 3.07 3.780 18.00 0 0 3 3 3.780
Cadillac Fleetwood 10.4 8 472.0 205 2.93 5.250 17.98 0 0 3 4 5.250
Lincoln Continental 10.4 8 460.0 215 3.00 5.424 17.82 0 0 3 4 5.424
Chrysler Imperial 14.7 8 440.0 230 3.23 5.345 17.42 0 0 3 4 5.345
Fiat 128 32.4 4 78.7 66 4.08 2.200 19.47 1 1 4 1 4.080
But, say that I'm working on a very large data with quite a lot of variables, and I want to just use a vector of strings like x1 = sprintf("xval_%1.0f", 1:25) where x1 will be the list of variable columns I want to run pmax and pmin with. But when I do this, then I'm always given an error message that confuses the number of vectors with the number of observations. For instance, say I run the following:
values = c("drat", "wt")
mtcars %>% mutate(maxval = pmax(all_of(values), na.rm = T))
Then I get the following error:
Error: Problem with `mutate()` column `maxval`.
i `maxval = pmax(values, na.rm = T)`.
i `maxval` must be size 32 or 1, not 2.
Which seems to be getting at the number of observations (32).
CodePudding user response：
We may use invoke (similar to do.call in base R) with across
library(purrr)
library(dplyr)
out <- mtcars %>%
mutate(maxval = invoke(pmax, c(across(all_of(values)), na.rm = TRUE)))
# or use do.call
# mutate(maxval = do.call(pmax, c(across(all_of(values)), na.rm = TRUE)))
-output
> head(out)
mpg cyl disp hp drat wt qsec vs am gear carb maxval
Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 0 1 4 4 3.900
Mazda RX4 Wag 21.0 6 160 110 3.90 2.875 17.02 0 1 4 4 3.900
Datsun 710 22.8 4 108 93 3.85 2.320 18.61 1 1 4 1 3.850
Hornet 4 Drive 21.4 6 258 110 3.08 3.215 19.44 1 0 3 1 3.215
Hornet Sportabout 18.7 8 360 175 3.15 3.440 17.02 0 0 3 2 3.440
Valiant 18.1 6 225 105 2.76 3.460 20.22 1 0 3 1 3.460
Or may use exec as well
out2 <- mtcars %>%
mutate(maxval = exec(pmax, !!! rlang::syms(values), na.rm = TRUE))
-output
> head(out2)
mpg cyl disp hp drat wt qsec vs am gear carb maxval
Mazda RX4 21.0 6 160 110 3.90 2.620 16.46 0 1 4 4 3.900
Mazda RX4 Wag 21.0 6 160 110 3.90 2.875 17.02 0 1 4 4 3.900
Datsun 710 22.8 4 108 93 3.85 2.320 18.61 1 1 4 1 3.850
Hornet 4 Drive 21.4 6 258 110 3.08 3.215 19.44 1 0 3 1 3.215
Hornet Sportabout 18.7 8 360 175 3.15 3.440 17.02 0 0 3 2 3.440
Valiant 18.1 6 225 105 2.76 3.460 20.22 1 0 3 1 3.460